Suggest Treatment For Thick Foreskin Along With Pain On The Penis

hi there i have recently had sex for the first time , and my foreskin was not moving yet. After sex it was fine but when we got in the shower and got out it rollled back on its own and the full head of the penis came out. it was sore and we went to bed but when we woke up it was swollen up with some fluid inside . it hurts rubbing off my pants or anything at all but i went to see a doctor at the hospital and she told me to just force it back over the head and it would unswell. i did this the swelling went down and the foreskin is now rolling back adn forth but it will not stay over the head of the penis. it keeps slidin back on its own can you help me please