Eye redness and irritation

I was diagnosed with OAG about a year ago at age 39. I was prescribed Brimonidine and Dorzolamide timolol. Taking both of these twice a day. Both these drops have kept my pressures in a normal range. My local eye doctor will take them by machine and they almost always run over 20 IOP in each eye and when they take them manually the generally range just under 20 IOP each eye. I am also seeing a GS and they take them manually every time and they have never got a reading over 17 IOP each eye.

Is this unusual or do GS have better equipment to read IOP?

Back to the redness/irritation. I really have had none to minimal issues with irritation and dry eye until about a month ago where both my eyes just flared up red. I saw my family eye doctor and he prescribed prednisolone eye drops 4x daily, and gave me some retaine PF eye drops, and retaine night time ointment.

I have not taken the Prednisolone eye drop yet as I am scared to run up my IOP and cause eye damage. I go see my GS on February 20th, and he messaged me and said it would be okay to take Prednisolone and we could change at the next visit.

Does anyone use Retaine and does it help bring down the redness and irritation?