Hi,
I'm not sure where you mean by 'right side'.
During diagnosis I got a huge pain in my right hip while walking and could hardly walk for a few days, it lasted for months although getting less severe. From time to time it still niggles.
Also I realised that I'd had a small niggling pain in my hip for a few months to the extent that I'd adapted the way I got undressed without realising it.
I was told that everyone blames every pain on the condition but it very rarely is.
I was convinced it was advanced PCa but they said it was a 'sports injury'. About 6 months later the GP said it was likely to be arthritis and gave me strong Ibuprofen cream. I wasn't convinced but the urologist later said my psa was still undetectable at my second appointment and such a long standing pain would be showing something up by then.
If your psa is very low a spread probably wouldn't show on a scan. Waiting between psa tests is perhaps your best proof.
Something else that I get and have heard it's associated with the op, is what I think is sciatic nerve pain. About once every 9 months. That is extremely painful, if it didn't go away after about 10 seconds it would be very worrying as it's the biggest pain I've ever felt. It's like a super cramp.
Let's hope your pain is just part of life after having had treatment. To me it's all trivial unless the psa starts to rise then it will become something else. Although if the sciatic pain stayed on I might change my mind.
Regards
Peter