Burning sensation in left boob- anyone?

PC • Mama to Cruz born 2/5/17 💙 expecting little princess Kaia 3/16/19 💖
When laying down the past week, I get sharp burning sensation only in my left boob. Lasts for 2-3 seconds and then goes away. If I move, it comes back. I've done a self breast exam and there's nothing out of the ordinary but I feel it's not normal. TTC #1, taking ConceiveEasy prenatals. Any thoughts or experiences like this?