I need help please give your opinion on my situation?

im a 13 year old female...i had a guy who was 20...i lied 2 him about my age n told him i was 16...anyway as time went on we got 2 know each other...even though he knew i was under 18 he still hung out with me...ummm we wound up having 1 night, no condom or anything...he left a hickey on my neck....when my best friend found out what happened she told the school counselor....the counselor called my mom and told her everything she knew....they tried to get me 2 give info on him but i wouldn't tell them anything....the school called the cops and filed a report i told the police officer nothing happened between me n this man....this guy that i was with hasn't heard from me since he got a text saying 2 change his number n that the cops are after him...i think i might be pregnant(im not sure) if i am im not gonna tell him because i don't want him 2 go 2 jail 4 coming 2 see me...please give your opinion, i've really screwed up my life and i just want help to figure out what i need 2 do now.