A couple days ago i went to the er (chest tightness) and everything came back normal, ekg etc. today i went back and i have inverted t waves. blood ok?

EKG changes: Hmm. If your 2 EKGs are different there could be multiple explanations. A different physical position Sitting/reclining/laying flat will all change an EKG. Lead position is also important. On the other hand, an EKG is often insensitive to cardiac damage (misses maybe 15-20% of small MIs). I think you should see a cardiologist to be sure. If you get any more chest symptoms go to ER now.