Is this hocd or am i in denial?

hiya im 20 and a female im goin to start from the verry begining of my problems... so i was 17 and i met this boy i really liked him i aint the kinda person to sleep around but i dont have a problem with people who do. i just always wanted to sleep with the person i was goin to be with. so any ways i ended up sleepin with him a few times them he f****d me off for this other girl i was so angry and upset but what could i do... it was a week after that when i met my boyfriend things was goin really good and i totaly forgot about that other boy.. but after a couple of months it all hit me i was sooo worried about tellin my boyfriend that id slept with him but i felt like i had to.. hes like me to he dosent think girls should sleep around . we nearly finished over it but we managed to get thru it. than after that i worried about everythin thinkin if he new curtin things about me he'd finish with me.. even things that didnt even matter id worry about then i got over that then started thinkin about other boys thinkin do i want to be with any one else but i new i didnt i just couldnt get it off me head and i went thru all differant things like that then in january 2009 i started thinkin that i still had feelins for that boy i slept with and i totaly paniced i was in a rite state it was like somethin just hit me and i couldnt get out of it then it moved to verious people n alls i remember i was layed on my bed thinkin whats rong with me n thats when it hit me am i gay....... and from that day iv dun nothin but worry iv dwelled on it that much ir feels soo real iv spoke to my boyfriend aboout it and he said its all in my head but i just dont no i just want to go back to the normal me but i feel like thats gone my mam and dad said i aint.. but i feel like what ever's goin on with me i just dont no any more i go thru staged wer i carnt stand it i'd just lay in a ball crying im on citellepam at the minit and its helpin but because i dont feel the way i used to its makein me think its even moe real. it makes me feel like i carnt feel my boyfriend any more im question if i even love him any more but i do coz i wanted to spend my life with him before this i mean iv always been attracted to guys so how can that change all of a sudded... sorry about the spelling mistakes just hope some one can help me please xx