I have a few questions. I hope I'm not going crazy but I get this weird feeling that goes down my body. It's usually out of nowhere & I feel like I can't breathe, my chest feels tight, I get lightheaded, my heart races and I for some reason think I'm dyin

Need examination. Your symptoms are consistent with several things EXCEPT going crazy. Nor do I think you are dying. But you should be checked for a few things such as asthma, allergies, bronchitis, etc. that should be tested and examined for before we can know exactly what's going on. You are welcome to send me questions to answer or set up an appointment for a consult at www.healthtap.com/drsaghafi.
Hyperventilation. syndrome: anxiety causing rapid shallow breathing with an associated rapid heartbeat and a sensation of impending doom. Some tricks to stop it: - rebreathe into a paper bag -immerse face into ice water ( diver's maneuver) -blow out as long and hard as you can -strain on a toilet like you are trying to have a difficult bowel movement. ( check Valsalva maneuvers to treat hyperventilation.