Not the tranny dude!

Today I pulled out on a main road my car was laggin going 20 and slowly slowly climbing. I pulled into a parking lot my car wouldn't climb past 2,500 rpm's. turned the car off then pullled back out and it was fine I pulled past 5,000 1st, 2nd, and third gear. My happens when its hot and cold when I first pull out or sometimes when im stopped at a light or something. This moring I was going up a incline on a road to work and I had no power to even get up man I was lagging hard 20-30 and couldn't go any faster.RYounk007 yours a 95 too?