Not even sure if this is Lupus related?

Hoping you all can help me. For the past month I've been getting a fluttering sort of pressure right in the middle of my sternum. Not only that, but when it happens I get the same feeling in my uterus. I have an IUD and I know it's not costochondritous because I have that and it's a very different pain. I do have post nasal drip lately and don't know if that's causing the chest flutters some how. Hopefully you all have some insight. Thanks!