My girlfriend said something that really bothered me...

So I (28M) was having sex with my girlfriend (26F) and she said "don't worry, I'm on birth control". <br><br>I don't have a problem with her being on birth control, but I find it strange because we've never talked about her being on birth control before. I asked her about it afterwards, and she said she's been on it for months and just forgot to tell me.<br><br>I don't know what to think of this situation, but it definitely made me feel weird.