My Mom has GERD and here in Brazil, we usually use omeprazole (omeprazol), because it's a cheaper medication.
About your trembling and muscle fatigue I feel like this most of the time, but it's 'cause I have too many spasms happening in my body. Still just with fibro diagnosis. But you should look for a good neurologist, if you have the chance.
Wish you well, Suzanne.

Also space all meals at least three hours apart. And don’t eat 2-3 hours before bed

I don’t take that medication but the trembling could be from fibromyalgia or the medication.
Feel better/ god bless!

Thank you for responding! I can't take Omeprazole, so Famotidine is what i take now.

According to my neurosurgeon its called essential tremor