Should I tell my boyfriend , I slept in myex boyfriend but he my bestfriend too house?

my ex boyfriend broke up with me a month ago and few day latter he ask me if and him could be come best friend again like with use to be before I told him yes that we could. On Friday night he ask me if if me and him can have some fun, I told him okay that we can h have fun but only as friends but some how I end up sleeping with him in he room but I don`t think nothing bad happen to us? those this thing count as cheating but if does I did meant to cheat on my boyfriend with my ex boyfriend plus best friend. how ever I think my ex set me up in a trap because after the break up he mean send love song , love poem and he was telling he wanted me.

If you are in highschool you can be friends with your ex. If not your looking for drama and get ready for emotional heartbreaks and crying. True story