First off, you should NOT be handling a snake that's "in shed". You're adding a lot of stress & doing no favors for his skin either. He's hiding for a good reason,
leave him alone, but do make sure he has a good sized water bowl & you might mist his cage a few times.
Clicking sound when snake is in shed is likely nothing more than old skin coming off in the outer part of his nostrils...re-evaluate -listen for whistling, crackling or
clicking sounds- AFTER he sheds. If sounds persist after a complete shed, that may be an RI, but for now, let him rest & hide. If you must pick him up for anything
at least put his face to his bowl of water...he'll likely take a long drink of water while you hold him gently, IF you don't move & he feels he can trust you.
Also do watch for excessive mucus or bubbling around his mouth...these are signs of an RI that has progressed & needs treatment (vet help!) immediately, but
again, I mostly expect the clicking will stop after he sheds.
Brown spot appears to be a scab...re-evaluate after shed...it may be a raw wound again at that time & in need of a safe topical medication. In fact, it wouldn't hurt
to have some Vetericyn ointment on hand, I think Petco or other pet chains carry it. He probably rubbed his head on an abrasive cage top in previous home. It's
close to his eyes & brain...it's not something you want to get infected...I'd have the ointment on hand, personally, as the scab will likely come off with the shed.
It wouldn't hurt to give us a photo from other side of his face showing his other eye. I'm assuming it's just in shadow? but...?