What time is your appointment? If it is in the afternoon, I would call to request an early morning appt. tell them it is urgent. Hot spot spread quickly as you have already seen. My vet once told me that they usually save one appointment spot in the morning just in case for an urgent call. Also, seeing is believing so if you have their email, send this pic to him/her with the explanation why he needs to be seen asap. that should get you in sooner and justifiably.
If you have a cone, put it on him. Even if he isn't chewing in front of you, chances are he will during the night.
That does looks very painful.
Edit: Sorry, I just saw that the appt is mid morn. I would still call as soon as they open.
"If you can't see his soul when you look in his eyes, then you need a seeing-eye dog"
Last edited by Heartandsoul; 07-25-2018 at 09:43 PM.