Should a blood blister on the inner side of a mouth cheek be popped?

My friend, I can only speak from what we experienced a couple years ago. My daughter had one on her gums. Scared the you know what out of me cuz it shows up blackened! I rushed her in to the dentist praying it was nothing. The dentist said it was a blood blister because she ripped out her baby tooth too soon before it was ready. (The lil stinker wanted tooth fairy money! Lol!) Anyways he gave me the option of having him pop it or letting it pop on its own. I let it work itself out and it cleared up with in a month. We chose not to pop it. I would call your dentist for sure though. ☺

I've had them in the past, but have never popped one.  I think they heal better without a tear or puncture.

No you shouldn't pop it, it's annoying to have one in your mouth, but give it some time. Also rinising out your mouth with warm salt water will help as well.