difficulty levels

I hope I'm not the only one that deals with this but in superstar mode I am a LB. I started out on rookie difficulty and blew everyone out for 2 seasons and I mean blew out. I went undefeated for 2 seasons straight and won the super bowl twice. my team had nearly sacked the QBs on nearly every play and stopped the run to under 50 yards per game and probably only had 20 points scored on me in 2 seasons. I decided to put it up to pro level to give more of a challenge but the opposing team scored on EVERY possession and I mean every one. it was like the difficulty went up to all madden instead of pro. heck the ball carrier ran like the flash. am I missing something here?