Can prolonged use of Oxy affect your brain?

Haven't been here in a while...trying to keep busy and my mind off pain.
I've recently developed hip issues (I exercise daily); they're not sure if its bursitis or calcification. In any case, sometimes it makes my back issues seem very minor in comparison.
I've been on Oxy for years (first Percocet) and have developed an unusual feeling behind my left eye and when I raise my head (to look up or shave) I get a winded/anxiety? feeling like I can't breathe and will pass out). The doc can't find anything wrong after x-rays and ultrasounds. So this is issue #1 and I'm wondering if anyone else has developed this. There is an inner ear condition that results in folks not being able to put their head back in a hairdressers sink, for instance. I can't do that anymore (I used to get my hair coloured in the summer), but it's not an inner ear situation. Can years of Oxy use leave you open to mental problems (other than dependence)?
Issue #2:
Oxy doesn't work for very long anymore (taking 30MG every 5 hours) and am considering trying the Fentanyl patch.
Looking for any input. Tks all, B