Irregular periods 🙃

So I’ve noticed that since I’ve been sexually active these past few months that my periods have become irregular 🤔 I’m confused because is it a coincidence..? Or is there some other factor? Because I used to be pretty regularly until I started having sex 🤷🏽‍♀️ idk just a thought but if anyone knows what could be causing this plz help me out :) I’ll ask my doctor just to make sure but until my appointment maybe some suggestions would help 🤷🏽‍♀️