delayed display

im just learning how to use open GL and I want the user through menus to be able to click on the screen and either points on lines will show where they clicked. For some reason, when they click the screen for points, nothing shows up but when they click another point, the first one shows up and so on. I am using glutDispFunc and glutMouseFunc. I have glutPostRedisplay in my mouse function. Thanks

Could you post some of the suspicious code?