advice injury/EC im not sure?

As you remember winnie was diagnosed with EC and is on meds. His 28 days runs out at weekend and were back to vets on tues (earliest appointment to see if he needs another course of meds and perhaps get dental, if they do them when they are on meds)
Anyways its his back end that he has problems with his back left leg its as though its stiff and wont move freely. It came on very sudden went to vets fine had myxi jab came home he wasn't himself next day noticed limp.
He said it was his hip area and im still not convinced he has ec as vet says ec doesnt hurt its all done in his brain he wont feel pain.
Yet when hes trying to lie down hes in obv discomfort and has to lie with his back flat on floor legs behind him or out to side (not like heused to lie) and sometimes when he looks like hes really having trouble getting comfy he screws his fet up in to fists like hes in pain.
I really think its his back ive researched back problems and rbbits get hip problems later in life or from squirming which he done at vets.
If its Ec will it clear or go (it seemed to have got a lot better and then has went back down hill but then some days hes ok) and what are hip/back problems? Oh and he sqeeks a bit when you pick him up and then pop him down.
Hes fine in himself although not eating as well as he should but I think he needs denatl hence why booked in next week.

sorry any ideas?

It sounds much more like osteoarthritis to me

Has he had any Xrays ?

He is already on Metacam I assume ?

If so what dosage ?

no x-rays done. He normally is on a ml of metacam and when he was put on zantac and panacur and steroids she stopped that. Hes just on panacur now from tues gone so I started him back on metacam on thurs only 0.4-5ml as didn't want to suddenly up dose.
I tried to make appointment for him last week and the earliest they can see him is next tues which i'm pee'd about as she wanted him back this friday anyways.

Personally I would be INSISTING on him being seen today/tomorrow.
He is clearly in pain

I'm annoyed because I rang to book denatl for angel its 3 months tommorrow and get win in with her and the receptionist was like youll have to see vet first I said I dont need to as its in her notes i can just book her in so she said well earliest is 2 weeks away. so they want her to wait a good week after her due date even though its on records.
Think I will ring and try again. He is fine at mo running about being cheeky but later when he lies down youll see him shuffle about.

Sorry, I don't have any advice to add, but I hope you can find out the cause of Winnie's problem. Sending lots of vibes for Winston xx