Have a clutch question

[QuiQ240]

Yesterday, i turned on my car, went to go for first and the shifter would NOT move to first. Clutch pressed completely down, shift would not go into ANY other gears [inc. reverse.] I was able to pull really hard and got the shifter to go into second. No grinding or anything, just very very hard. I was able to move in 2nd and after trying really hard, was able to shift to 3rd, then decided to just park it. I turn the car off and the shifter moves flawlessly. Today I checked to make sure my slave cylinder was actuating the fork, and it is. Looked at the master cylinder, fluid is full. No visible leaks anywhere. No recent work has been done on the clutch, and there have been no other symptoms of any problems. I drove the car the day before [nothing aggressive]

Car is a 1995 240sx with a red top SR20DET. stock 5 spd.

I've done some searching, and only things i have seen suggested is a problem with the slave cylinder, but as previously mentioned, It appears to be actuating the clutch fork. I would appreciate if anyone has any ideas of what else i could check. I am on a very tight budget after recently replacing the transmission in my truck.