UNUSUAL DISCHARGE FOLLOWED BY IRREGULAR PERIOD.

hI im 18 sexually active in a serious relationship. About a month ago i hadunprotected sex w my bf but he put a condom on before he finished. The next day i had fishy smelling discharge but it was somewat mild, and later on i got an UTI and was gven medication. The uti cleared up then reacured the next week and was given another type of antibiotics. Thats when i noticed that i had alot more disharge than i usually had and it sometimes smelled fishy. I also had a couple of pregnancy symptoms such as morning sickness about 3 weeks after i had sex w my bf and my breast started getting sore as well as i was really hungry and i tired easily. Then this weeki really overdid it w having sex w my bf probably 5 times a day and i started getting ramping 3 days ago AS WELL as the fishy smell was still there. Today i woke up w sever cramping and went to the bathroom and had bleeding that came in like chunks of tissue .. a fewhours later as i stood up i felt like i peed myself but when i looked at my pad it was pure blood ...its been happening a couple of times now and my cramp[ing gets better after the blood comes out ... im really scared and dont know wat it is... i knw my period is light to moderate and i t was supose to come 4 days ago .. i took a pregnancy test about a week ago and it was negative so idk if its just an irregular period or if im having a misscarrige.. plus i dont know about the discharge that i had before....plz help!!!