Cycle Day #63

So I have been having super long cycles! My last cycle was 57 days long, and the doctors said it was just stress related. My current cycle is 63 days and counting! I have extremely boob/nipple pain! My nipples are so sensitive they hurt when the shower hits them, and my boobs feel like someone is constantly pushing on them, and they are super heavy! (Not sure if that makes sense) I took a pregnancy test today and it was negative, I don't know what's going on! Help!