So I'm On Birth Control And I Had To Switch

So I'm on birth control and I had to switch from my old one to a newer one because the old one was not strong enough(I was going on vacation and did not want my period also I am a virgin) now with my new one, I've been on it for about 8-9 months and sometimes my period doesn't come or is extremely light, so does that mean it's very strong?? I'm asking this because I am wanting to have sex and he doesn't have access to a condom and he is going to pull out but I do not want to get pregnant.