Grand am A/C problem

I have a 1995 Grand Am 3.1 GT. The air conditioner is not blowing cool. I can see and hear the clutch engage, but still won't get cold. I have put R134 in it and an oil charge. The pressure guage I have is not working correctly I don't believe , becaus it still shows 25lbs and holding. It showed that after 1 can and still after the 2nd. Don't think there is a leak because it still showed the same after about 30 hours between cans. Does it sound like I may need more freon or is there something else I may need to look for?

Welcome to AF.

Maybe something else in the AC system not functioning.
Best to take it in and have it checked out by a qualified technicain.