Weird air bubble feeling in upper chest

Hi everyone! I have managed to avoid COVID until I tested positive on Friday. I had some weird sharp pain that felt like an air bubble right under my sternum. I went to the urgent care and they really couldn’t do anything for me. I also randomly vomited once on Friday, but haven’t felt nauseous before or after. Tonight the air bubble feeling has come back. It’s a very sharp pain that comes and goes right under my sternum. It doesn’t feel like bubbling, just an air bubble that stays. It doesn’t matter how I breathe or what position I am in. I don’t feel nauseous either. These are the only two symptoms I have.