Long cycle out of nowhere?

Br

I've never had long cycles before. I had irregular cycles when I first got my period at 10 years old and was able to take birth control to regulate it at 14. After about 6 months or so I stopped taking them because they made me gain weight like crazy and for other reasons as well. After I stopped my cycles were regular, and I started taking birth control around December of 2017, but I wasn't consistent after a few months. After I met my SO I decided to get off of the bc in October of last year and my cycles were still fine until March, my periods lasted for three days and then in April it lasted for four days and the cycle was 29 days long. Now this month I ovulated late and it's now cycle day 35. What. The. Hell. Is going on. With my body.