Re: Possible mouth injury?
Mine did something similar this spring, he's 5 and fasts every winter. But he was suddenly ravenous around March 20th and I went to get his rat warm - he was sooo ready to eat that he struck the glass door of his cage before I could open it! He immediately squirmed back and forth like it hurt and retreated to a hide, he didn't come out voluntarily for two weeks. I checked his mouth/face and there wasn't any obvious wounds but I imagine it was bruised. He eventually ate and the incident was forgotten.
I think the pain response is strong in reptiles and when something hurts they avoid it from then on, but re-learn that everything is ok as long as the negative stimulus isn't repeated. I've heard of pet ball pythons refusing certain color of prey if a live one attacks them; my male gecko go bit under the eye by a particularly feisty superworm two years ago and STILL refuses to go near them
Re: Possible mouth injury?
My boas have a habit of striking the acrylic doors in anticipation of food. The worst that's happened in 4 years is Behira, my female BI, bent a tooth and it fell out.
Unless there is noticeable damage, I wouldn't sweat it.
However, as mentioned, your BP could have been spooked and then to eaten that time. Wait until next feed and see what happens.
They can absolutely damage themselves striking the doors or tongs, etc. However, they are also pretty tough. Stay on top of it but otherwise, don't worry too much.