How to tell my boyfriend.

I have been with my boyfriend for almost 2 years. We have been off and on talking about wanting or not wanting more kids. I have one from a previous relationship and he has one from his previous marriage. I was on the pill and we had sex the weekend before Valentine's Day. Well he didn't pull out of course and I haven't had my period. I was suppose to start my period Monday so since I didn't start I took pregnancy test that came back positive. Just last week he had told me that he for sure knew he didn't want anymore kids. Which I was already considered pregnant then just didn't know. So anyone have any advice on how I can tell him and hopefully it won't change things between us. It wasn't like I was meaning to get pregnant but GOD is the one that's in control and he thought it's what we needed. I think a child is a gift, you just don't always get it when you have unprotected sex. Advice or helpful thoughts?