Birth Control & Period

So I had been on birth control since I was 18. I wanted to see how my body would function without it so I decided to stop taking birth control. I’m 24 now. I had a pretty normal first period off of birth control. Now I’m waiting to start my second period off of birth control. Is it normal for it to be unpredictable right now? Also, I had sex a couple of weeks ago (with a condom) and now I’m freaking out lol