heartburn from lifting?

So i feel stupid asking this... but just recently i've started trying to do a little heavier lifting... not HEAVY... but say, using 2 10lb dumbbells instead of 5s. And for the past two weeks I've had what sort of seems like mild heartburn. Not that awful, wretched heartburn like I had constantly when I was pregnant but this really mild, sort of just feeling like a lump in your throat little burn. And i'm really freaked out about it.
Is it normal to develop hearburn/GERD from lifting? even that little weight?

I know I can ask my doc... but I think you guys would know better. Thanks!!