Abscess? Can anyone look at these photos and give me their advice?

Just to help ease my mind about it for a bit, until tomorrow when I can call his vet. This is my cat Moscow, he's 8 years old, indoor cat. Over the last few weeks he had a food allergy causing him to lick around his face, neck and back. (As you can see on his lower neck in the photo he is regrowing the hair).  I realized it was the food causing this so I removed it and gave him something different and his coat definitely improved. I noticed a week ago his eye (the same eye in the photo) was a little droopy and swollen, but because I was told he has allergies I left it at that and in a few days it cleared up. The same eye is swollen like that again (as you see in the picture). Let me just note that when he was having the food allergy he was losing weight and only just recently (maybe the last two weeks) he has gained a little back. But he still eats, drinks, does everything else normally.

In total I have three cats, including Moscow, and he's my oldest. The other two cats play with him, but one cat gets a little too rough so I know the wound he has is from her. The wound is on the middle section (under his chin) I'm hoping the pictures will help. Do you think this could possibly be an abscess? 

I have never dealt with a cat who has had an abscess and when I noticed his chin was all swollen I started looking online and well, we all know what that does, so I'm a little worried. More than likely he won't be seen until Tuesday, as he will go to the vet tomorrow (in the afternoon) & they will keep him over night since he is the kind of cat who will need sedation. So Tuesday will be the day that he will be able to be touched & looked at. 
I circled in red where the pink wound from the fight is, everything else under that wound is swollen. 

Also to be safe I did check his teeth and nothing seemed to be wrong there either. Just wasn't sure if this was an abscess or not. I will definitely update everyone after I have spoken/seen his vet. Please any input or experience with something similar would be appreciated... this has me worried

It certainly does look and sound like an abscess but only your vet can say for sure.  With the squinty eye, though, I wonder if it isn't a tooth problem, even though you said his teeth look okay.

Make sure your vet knows your concerns and hopefully they won't wait until Tuesday to check him out.  Is there any way to contact them over the holiday?  Perhaps there is some pre-care such as discontinuing food after this evening that you can do, so that they can sedate him tomorrow and get him looked over.

Put a warm compress on it until you can get him to the vet. 

I had some clindamycin left over from when he was licking himself raw from the food allergy---MASSIVE difference!

I am still taking him tomorrow, but theres no more swelling and he looks fine. He was cuddling up close to me and he has other sores around his face...near his mouth and up by his ear.

I will still update after tomorrow but..that antibiotic that I've given has helped a lot.

Thanks sooo much for the responses. I feel more at ease!