What Could It Be ? Hormones ?

Ally

So Since the 2nd I been feeing sleepy but I think it's just due to hormones since I just got off birth control pills and it's around ovulation . It's a day after ovulation and I still feel sleepy and my upper back hurt . I had sex on the first but I know it's too early to be pregnant so is it just hormones ? I also had sex on the 5th of February but my cycle came