Hey Doc.! .I've Been Recently Experiencing A Popping In My

Hey Doc.! .I've been recently experiencing a popping in my left ear. I'm a little worried because it happens when i have to belch and instead of making them loud I keep them in and then exhale(get it?) When I yawn to try and pop them both like on a plane only one pops like normal. Could this be a sign of going deaf or cancer? I can still hear out of it, the popping is just driving me crazy!