My irregular period.

I’ve been having an irregular period that can last for weeks and I’m sick of it to the point where I’m uncomfortable in my own body. I’ve been in and out of doctors offices and they’re trying to figure out what’s wrong but I can’t wait any longer. I made an appointment to get birth control to hopefully stop my period. I’ve been on the pill many years ago and it stopped my period almost instantly. I’m scared to be on BC because I do want kids and I’ve heard all these stories about BC messing up women’s body making it harder or impossible to have kids. But idk any other option. What should I do?