Sore boobs?

We’re not TTC yet. I’m still on my BC pill as I have for 18 months now. I’ve gained 10 lbs over 4 months now...just me not watching what I eat.

Anyway, I’m not pregnant yet or any chance. My boobs have been sore for a few weeks now and I’m wondering if it’s because I’ve gained weight and it’s now bothering me? Or anything else?