My baby's penis is ballooning during peeing. Is there anything to worry about?

Hello doctor,

My son who is 2 months old sleeps longer during the night now and urinates very less during the night (one or two times only). Yesterday, he went without peeing for about five to six hours at night. Since few days he is also crying when urinating (before and after as well). His penis is also ballooning during peeing and at times it seems like he is straining or pushing. He does not cry always also when peeing. I showed a doctor about the ballooning and pain and he looked at the penis and told that his skin is too tight and the hole is small. He told to push the skin back and apply an ointment (Fusidic acid based) after bath. I just applied it once as I am not sure about pushing the back skin and the ointment itself. We also did a urine routine today and everything is nil (pus 1-2 /hpf and epithelial 2-3 /hpf). Is there anything to worry about? Please advice. It is very hot climate here right now.