You need to discuss this with your medical team. Tell them everything you said here they need to sort through and figure this out. I usually am not in constant pain but I do take various meds for my various ailments. You can't sort it out you need medical help.

I'm not in constant pain unless I am in an uncontrolled flare up.

Good answer, jaml. My Fibro is so bad now (I think it's progressive) I'm always hurting somewhere but not until about 3 years ago. I was diagnosed 20 years ago and until about 6 years ago I was able to hold a job. A Fibro diagnoses is a lot of ruling out other disorders/diseases.

I'm in constant pain and have flare ups too. I'm not sure why and maybe there's more than one or two things more going on. Definitely keep checking. I'm finding out I have quite a few issues that cause pain. I don't remember what it's like to not feel some pain. Even pain meds don't help fully, just reduce it.

It is very true that it varies from person to person. The symptoms u experience, the amount, n type of pain u have is ever changing.
If ur dr n insurance will agree to an MRI, theres no harm in having one done - if it will ease ur mind about Parkinson's.