Lynnette,
I do not know what county you are in but if there are many articulation mistakes in yous son's speech PLEAS call Babies Can't Wait in your area. They may be able to do a better speech assessment than the one you went to.
My daughter was 2.5 yr old and she did not talk well at all. Had the same ear problems and a Binky past the age of 2 so part of it was my fault (the Binky) but the ear stuff is NOTHING to take lightly.
If your son cannot hear properly, then he won't speak properly.
As far as him knowing colors and things like that... he is still young and that will come with time.
My older child, could say the alphabet, numbers to 20 and his complete name at 2.5 yrs old but the other stuff came with time. He's 24 now and in college. Just don't sweat the small stuff, but check out Babies Can't Wait. Pre-schooler's age out at 3 yrs old.
Hope this helps,
B.
deaffmommie