It is a nature act to have sex but be sure the relationship. At the first time, did you get wet enought before inserting. Did your boy firend use a condom with lubircant?
Yours size and his size may be alittle problem for the pain but natually, vargina can extend as big as a head of baby.
So, having with your boy friend will be better if he learn how to do the gentel sex. He may rush to have sex before you are ready.
Be sure get married with him after sex and be sure he love you more than having sex for fun, if not he will leave you and have sex with the others