Puppy eye issue and growling

Hi all,
Had to give my 10 week old springer eye drops due to pink eye. Straight away he didn't like it. He wiggles like crazy when he isn't happy with something. He was the smallest of the litter and often was picked on, so maybe his wiggling came from that (the breeder named him wiggles). Anyway, my partner went to restrain him for the eye drops and he struggled, started growling and bit her a few times. Not hard but enough for her to feel it. I stopped trying to put the eye drops in straight away but my partner kept a firm grip on him. Her idea was to stop an association between bitting and getting the desired effect, which is us backing off. So the tough love approach. Afraid that this approach was going to escalate to more aggressive behaviour, I took over administering the eye drops. My approach was treats, treats and treats and basically very light resistance (basically just trying to stop him wiggling so much by positioning him on the sofa so he had less room to move) and patience. I tried having him on my lap and going from behind with the drops with no luck. I think I got more eye drops on his face than in his eye, but I did my best. His eyes now look ok, but he still gets a few eye boggers that I wipe away with cooled hot tea water, on a cotton pad. The whole ordeal was stressful for the both of us (I don't know how vets do it!). He did mouth my hand while trying to get the eye drops in, but he never growled and it was more puppy mouthing to tell me he wasn't hapoy than anything to worry about, such as growling or snapping. Unfortunately, I'm afraid despite my best effort, his eyes have now become and issue and he doesn't like me going near them, but treats and stroking his face gently across the eye area seems to be working with the idea to desensitize him. But, just now when I had him on my lap, he growled when I went to check his eyes. He was overtired and I think he felt restrant because he was on my lap. I gave home soothing rubs, spoke to home softly and stroked across his eye and he was fine. I guess my query is, will this reaction get better as he gets older when hopefully he has a better understanding that we are trying to help him? Or is this an issue now that we have to work on? I'm also hoping this aggressive behaviour doesnt bleed into anything else, for example getting his collar on is become a problem and all the treats in the world ain't changing his opinion that it's a torture device. He has had it on twice and now we may need to restraint him to put it on and that's where the issues lies, as restraint makes him aggressive. Any help or advice would be most appreciated