scratches and cuts should I be concerned?

I just put my peacock Gudgeons in my 29 gallon tank over the weekend. Last night the male got himself stuck in my HOB filter's pick up tube. Not the tube itself but there was a little hole above it that I didn't even know existed. It was about the size of a pencil eraser and he had his whole head in there. Only a PG would be skinny enough to fit it's head in there. I pulled the plug on the filter and he was able to squirm out but he had a big white spot on top of his head. I looked at him today and it's gotten bigger and there is some on the bottom or his head too. The scales are starting to peel off. Should I be concerned? Is there something I can do for him? Meds, hospital tank? I have been watching him and he is acting normal just a little scared hiding in caves and not exploring that side of the tank anymore.

I do 50% changes every week so that should be a problem.

i caught it literally withing a minute of it happening. He was swimming around in the tank and I turn my head and look back and he is gone. So I know it was a fast rescue. I agree I was thinking of catching him and doing a hospital tank thing but as long as he doesn't get it infected or get worse I am going to leave him alone. He found a big cave with a sword growing in front of it. So it's really dark and hidden pretty well for him.

He came out of hiding last night. still wasn't eating or swimming much. I decided it was time he ate something and with the other fish it was impossible. I netted him and put him in the QT tank so he would have no competition. Even though the tank was the same temp and the same water as the main tank he didn't like it right away. Within a hour he stopped breathing. So I don't know if it was stress from the move or I just waiting to long but he didn't make it. I am cursed with pairs. I had a pair of Long fin L144's. One died from Ich. My german blue rams turned into 2 males and had to get rid of 1. My 2 dwarf gourami's fought so much I had to get rid of one. Anything I buy in pairs doesn't work out. The PG's were really nice together though, swam the tank together slept near each other and always displayed to each other. I am tempted to get another male to replace this one but shipping for 1 fish isn't very logical.

I hope the place I got them from can get in stock something else I would be interested in. So I can do a larger shipment and save some dough.