Probably needs more root room, as its quite tall, so a bigger pot or in the ground. You can prune back - they don't like it much, and sometimes don't respond well, but usually they're fine if done around the end of May or early June. However, it would still be better to give it some new compost in a larger pot.

Is it a dose of epsom salts if they look a bit yellow?
We were advised to do that with the citrus trees and it seemed to help

Thanks, I would guess it does need a bigger pot,it's been in that one a number of years but so difficult to move around like I do when in flower so I can see it from inside the house.The soil in my garden is not the right kind and because they dislike the morning sun on their leaves there is nowhere suitable to put it in the ground in my small garden.....I will try Epsom salts Pam hadn't heard that before.

Many garden centres stock wheeled pot stands/caddies in a variety of sizes. As time marches on and my strength ebbs I have started to gradually introduce these into my garden. Wilkos stock some small sizes whch are fairly cheap, but I am on the look out now for larger/stronger and consequently more expensive ones for my bigger pots. Like you, I like to move the pots around too but my joints complain more often these days.

I'd be wary of applying epsom salts to an acid loving plant like Camellia frankly, particularly in a pot - its much more likely that the yellowing is down to cramped roots, so I'd pot on first into ericaceous compost, then give it a good ericaceous feed after pruning.