About Three Months Ago I Started Having A Lot Of

About three months ago I started having a lot of symptoms ( nausia, vomiting, frequent urinating, sore breast) of pregnancy. I got into an altercation with someone I lived with and was kicked in the stomach. The next day I started bleeding and cramping. But still having symptoms. Now I've been having my period a week late for two months and the cramps are very bad. I still have vomitting sometimes and sore breast. I went to the hospital twice and both urine test I took came back negative. Is it possible I could have miscarried and there is something in me affecting my body still? Is it possible the tests could have been wrong?