Does birth control cause irregular periods?

Hi wondering if anyone has experienced this. I stopped the birth control pills right at the end of February this year. I had a regular cycles after that. My husband and I are trying to conceive since then. Anyways this last month in May 26 I got my cycle like usual. A week after I notice some spotting. It was on and off for week. Then today I just notice I started having a heaving spotting like if I am starting my period but I am not supposed to get my period until June 22nd. I did had a cyst on my ovary but when I consulted with my OB in March to make sure I am 100% healthy to conceive she said I didn’t had it no more. However as far as I remember when I went for an ultrasound back in December to follow up about the cyst it had only shrunk. So I am not sure why my OB said I didn’t had it so I just left it at that. Now I am wondering what’s going on with me. I am 35yrs old. Anyways what has been anyone’s experiences with this and the outcome? Thanks