Had sex 2 times and fell pregnant

I recently just started seeing a new guy hes really nice and everything but whats happened is weve only had sex 2 times and ive just found out im pregnant very early. I dont know if i should tell him or not. I dont think he would believe me any way i dont know wether to keep it to myself i dont think its fair to do this to him after 2 times of having sex it might not be something he would be particularly happy about. Do you think i should tell him i want my baby and i want my baby to have a father but it might not work out between us so i may end up a single mum which im happy with and happy to do but i dont kbow if i should tell him