can't draw any other objects before or after drawing particles

Question

I am working on a game, and trying to implement the instancized CPU-Particle System programmed on http://www.opengl-tutorial.org/intermediate-tutorials/billboards-particles/particles-instancing/ i managed to get it working in my code structure, but i am trying to draw other objects in the same window, which i can't, i have tested it, and it only allows me to draw one, either draw the particle system or draw the object i want.

The problem happens specifically at this code part :

    glEnable(GL_BLEND);
    glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);

    // Use our shader
    glUseProgram(particleprogramID->programHandle);

    unit2 +=1;

    glActiveTexture(GL_TEXTURE0 + unit2);
    glBindTexture(GL_TEXTURE_2D, texture);
    glUniform1i(TextureID, unit2);

    glm::mat4 ViewMatrix = camera->getViewMatrix();
    // Same as the billboards tutorial
    glUniform3f(CameraRight_worldspace_ID, ViewMatrix[0][0], ViewMatrix[1][0], ViewMatrix[2][0]);
    glUniform3f(CameraUp_worldspace_ID   , ViewMatrix[0][1], ViewMatrix[1][1], ViewMatrix[2][1]);

    glUniformMatrix4fv(ViewProjMatrixID, 1, GL_FALSE, &mvp[0][0]);
    //glUniformMatrix4fv(modviewprojID, 1, GL_FALSE, &mvp[0][0]);

    //1rst attribute buffer : vertices
    glEnableVertexAttribArray(0);
    glBindBuffer(GL_ARRAY_BUFFER, billboard_vertex_buffer);
    glVertexAttribPointer(
        0,                  
        3,                  
        GL_FLOAT,           
        GL_FALSE,           
        0,                  
        (void*)0            
    );

    // 2nd attribute buffer : positions of particles' centers
    glEnableVertexAttribArray(1);
    glBindBuffer(GL_ARRAY_BUFFER, particles_position_buffer);
    glVertexAttribPointer(
        1,                                
        4,                               
        GL_FLOAT,                         
        GL_FALSE,                        
        0,                               
        (void*)0                         
    );

    // 3rd attribute buffer : particles' colors
    glEnableVertexAttribArray(2);
    glBindBuffer(GL_ARRAY_BUFFER, particles_color_buffer);
    glVertexAttribPointer(
        2,                                
        4,                                
        GL_UNSIGNED_BYTE,                 
        GL_TRUE,                          
        0,                                
        (void*)0                          
    );


    glVertexAttribDivisor(0, 0); 
    glVertexAttribDivisor(1, 1);
    glVertexAttribDivisor(2, 1); 

    glDrawArraysInstanced(GL_TRIANGLE_STRIP, 0, 4, ParticlesCount);

    glDisableVertexAttribArray(0);
    glDisableVertexAttribArray(1);
    glDisableVertexAttribArray(2);

then i try to draw my star:

unit2 += 1;
    starTexture->Bind(unit2);
    shaderObject ->useShader();
    glUniform1i(glGetUniformLocation(shaderObject->programHandle, "colorTexture"), unit2);
    glUniformMatrix4fv(glGetUniformLocation(shaderObject->programHandle, "modelMatrix"), 1, GL_FALSE, glm::value_ptr(star1->getModelMatrix()));
    glUniformMatrix4fv(glGetUniformLocation(shaderObject->programHandle, "projectionMatrix"), 1, GL_FALSE, glm::value_ptr(projectionViewMatrix));

    star1->draw();

the vertex and fragment shader for the particle system:

    #version 330 core

// Input vertex data, different for all executions of this shader.
layout(location = 0) in vec3 squareVertices;
layout(location = 1) in vec4 xyzs; // Position of the center of the particule and size of the square
layout(location = 2) in vec4 color; // Position of the center of the particule and size of the square

// Output data ; will be interpolated for each fragment.
out vec2 UV;
out vec4 particlecolor;

// Values that stay constant for the whole mesh.
uniform vec3 CameraRight_worldspace;
uniform vec3 CameraUp_worldspace;
uniform mat4 VP; // Model-View-Projection matrix, but without the Model (the position is in BillboardPos; the orientation depends on the camera)

void main()
{
    float particleSize = xyzs.w; // because we encoded it this way.
    vec3 particleCenter_wordspace = xyzs.xyz;

    vec3 vertexPosition_worldspace = 
        particleCenter_wordspace
        + CameraRight_worldspace * squareVertices.x * particleSize
        + CameraUp_worldspace * squareVertices.y * particleSize;

    // Output position of the vertex
    gl_Position = VP * vec4(vertexPosition_worldspace, 1.0f);

    // UV of the vertex. No special space for this one.
    UV = squareVertices.xy + vec2(0.5, 0.5);
    particlecolor = color;
}

frragment shader:

    #version 330 core

// Interpolated values from the vertex shaders
in vec2 UV;
in vec4 particlecolor;

// Ouput data
out vec4 color;

uniform sampler2D myTexture;

void main(){
    // Output color = color of the texture at the specified UV
    color = texture2D( myTexture, UV ) * particlecolor;

}

and it only displays the particle system:

worth mentioning is: the object i want to draw is a star modelled in blender and is displayed correctly when drawn alone or with other objects other than the particle system. and has its own class having buffers for psitions, UVs, indices and normals...

it seems like the star data are being swallowed by the buffer...

i appreciate every help...