Help me figure out what im doing wrong? I'm 21, i exercise con...

Help me figure out what im doing wrong? I'm 21, i exercise constantly, I have never had children. i have what I'd like to think of as "a very healthy normally functioning uterus". extremely regular periods, barely get any cramps. I'm in great health, except i drink and recently picked up smoking . I got my Mirena inserted 3weeks ago exactly. this is my mini journal: 1st day:(3/16/09) got it inserted and they gave me antibiotics to prevent infections. i had very light spotting and mild cramping. Advil did the trick 2nd& 3rd day: like nothing ever happened. i was feeling great. 4th day: I finished taking my antibiotics.I bicycled for about 2hours. i got home and i had cramps more painful than usual. spotting got darker 5thday: (4/20/09) i had a very sharp pain from the bottom my ribs cage to my belly button felt like my organs in that area where gonna pop or like someone punched me really hard. i had a drink that night and it really didn't help. it would come and go all day. spotting was heavier but not dark 6thday: (4/21/09) it was my 21st birthday so naturally i had to drink but i was really hesitant because i still had the same pain. i had a couple drinks smoke a couple cigarettes and the pain went away and never felt it again. spotting faded and was pinkish color (4/22/09)-(05/02/09) to pain no nothing spotting was becoming clearer over these days 05/03/09: was my friends birthday party I walked around town everywhere. i had no car and no bike and i had to run errands for the party... grocery store, bank,...everywhere! my legs were so sore when i finally got home. at the party and had maybe 3 drinks and smoked a lot of cigarettes. the next morning i was woken up by in the worst pain ever (i wasn't hungover) its felt like someone was sticking a knife up my vagina into my uterus. i was bleeding a lot and it was really dark i was in tears. i didn't have ANY type of aspirin or anything at the time. it would come and go for about 3-4 hours. finally i got some Tylenol and the pain went away haven't felt it since. 05/04-today: drank,smoked, no exercise, no pain, since then spotting is almost clear now im wondering if the pains or cramps were from really from excessive exercise? does that mean i cant exercise now or ride my bike? :(