Confused

Alright this is my first time ever posting on here but I’ve been thinking about something and I haven’t really talked to anyone about this so I’ll just tell you guys. I’ve been thinking lately that there is something not physically but I think internally wrong with me. I’m under the impression that I can’t have children. I haven’t been told by a doctor or physician that I can’t I just feel like I can’t. I’ve been off of birth control since my junior year of high School because the method I was on was the Depo and I didn’t like it because I gained so much weight during it. Anyways I’ve managed not to get pregnant for the past 4 years without any protection or birth control. My boyfriend and I don’t use condoms on a daily basis, hardly at all honestly and I’ve managed to avoid it till now. Meaning I’ve decided to try out the new method of the BC that’s implanted in your arm. I know that alone doesn’t mean anything it could all just be in my head but my mom and sister have been known to be really fertile and easily got pregnant without being on birth control but always been less than a month or two before they ended up getting pregnant afterwards. I don’t know if I should bring it up to my doctor tomorrow when I go in to get my implant injected or if I should just forget about it and stop worrying about something that probably isn’t even a big deal. I don’t know what I should do. 😒