Behavioural problem or UTI problem

Could you please be so kind and give me your opinion regarding behaviour of my male cat?
I have British short hair colour point mail cat aged 1,5 year. He is not neutered since he had bitten himself few days before the surgery.
He had bitten his genitals (Where He Pees) and wounded himself badly. Veterinary found that he has struvite stones, he received antibiotics and special diet – Hill’s c/d. He had difficulty with peeing so he had to be catheterised at that time. He had to wear E-collar. After that he had no problem with peeing. After several days I was suggested to take off his E-collar, and he had bitten himself again (same place). He received for almost 1 month antibiotics and bitten himself again when I took off his E-collar. Veterinary than took urinary culture and diagnosed he has MRSA and cat received 10 days special antibiotic treatment.
My cat is very affectionate and calm. I used to feed him with Hill’s wet food and Orijen and Granatapet dry food before this. He had no health problem before this. I clean his litter daily and I use Ever Clean non scented clumping litter. He is now on special urinary diet. Could you please tell me if his behaviour is result of the pain or it is some other issue?
Thank you for your answer.

Yes, it does seem that he is biting himself as a result of the discomfort associated with the infection/crystals.

I see he is in c/d...is he on the wet or dry food? If not already on canned only, I would suggest making the transition.

It does sound like he is biting himself from the pain, my heart goes out to you both. I pray you can get him healthy again and go back to a normal life!

Thank you. I give him wet and dry food and I have bought fountain so he now drinks more water. I have tried to give him raw food but he is very difficult and did not want to try

Thank you. My veterinarian suggested that it could be behavioural problem and is looking for some medicine for depression. It is hard to believe for me that he is depressed or frustrated. I think he would show other signs of frustration and I don’t see any.