Clutch acting weird! HELP!!

so i was driving my rx8 this morning and everything was perfectly fine. After getting out of school, I was driving to work and I noticed that as I would take off, after putting it in gear, the car would take off but if I were to give it gas to take off quickly the rpms would go up and the car would move slowly. It was acting as if I was pressing on the clutch while in gear. So in order for me to get going I couldn't give it to much gas and would have to let the rpms adjust to my speed. Is it my clutch going out? I had recently put a new clutch petal on it about a few months ago and thought that maybe the bolts were loose on it and made it not have enough clutch play but I checked it and that doesn't seem to be the problem. Break fluid seems to fine for the tranny. Any suggestions?

Thanks in advance!