Heavy bleeding during pregnancy

Okay, so I took a total of 5 pregnancy tests, and 2 came back neg. and 2 came back pos. but I was under alot of stress, and I happen to be pregnant for 5-6 weeks. I conceived in early september and and found out I was pregnant on october 12. I remember doing alot of chores around the house, and I had sex with my boyfriend because I always heard it was safe to do while you were pregnant. I felt some pressure and pain during sex. and the following week my boobs did not hurt anymore but they are still swollen. I was/ still concerned I have had a miscarriage and I woke up the next morning with some cramping, vomitting, and menstrual like bleeding. I also took a test LATE in the day and the test came back negative.. I am really concerned that I lost my child. I still feel some what pregnant, but yet I feel alot of greif. is there a possiblity that the baby is alive??