I do understand your hesitation and it is something that has worried me from time to time, but in practice it has never been a problem. I still remember with gratitude two GPs, on separate occasions, years ago, who grasped that I was in pain, described to me what was going on and prescribed painkillers. I asked which combinations I could take and got clear answers.
For chronic conditions, I find that describing the pain and asking for help has always worked, with the exception once of a trainee GP who insisted on asking me what I wanted, and all I could think of was Oramorph, which she prescribed. In fact I needed advice but she was in “ask the patient “ mode.
There once was a locum who didn’t seem to understand that I have a chronic condition that was flaring, so I went back the following week and luckily saw someone else.
I have cocodamol on repeat prescription but recently I put in a request for diclofenac gel, because other medication has had to be reduced. I explained why I needed it and it was prescribed. I had to go back and explain why I need the max strength and the prescription was adjusted: I think they’d just not read the request properly and I explained that I am buying it, but it’s expensive. In fact I’m still subsidising what is prescribed with a bought tube as 1 a month isn’t enough.
Sorry, this is long winded, but I think they’d bottom line is to explain the problem and ask for help, being ready with a suggestion in case you’re asked.
If you’re being treated at hospital, they sometimes have a helpline in the particular department.