I'm currently taking birth control meds and noticed that my periods are starting late and are spotty. Also my breast are sore, and I'm constipated. What should I do

That's normal didn't your doctor explain that to you?

What do you mean by spotty? Like spotting between periods? Or just very light periods?

As for the sore breasts-that's definitely normal. I find that midol or advil helps. Maybe switching bras around that time of the month too. As for the constipation, really pay attention to the foods you're eating. Make sure you're getting a good amount of fiber. Certain foods will keep you more regular than others.