I have head pressure with low concentration and neck pain. Are these related to brain problem?

Hello doctor,

I have general head pressure (or tension) and I suspect brain problem. GP seems to treat my symptoms as we struggle to find the root cause. My concentration level seems impaired, though not severely. I get feelings like I would pass out at times.

I get weak joints at times (hands, knees, etc.) perhaps slight tremors when the pressure is severe. The hemoglobin value was 15. I read that thyroid could cause brain issues, but I have not tested for this yet. I get lower left neck pain or tension at times. I have taken PPI for ulcer and read that it can hinder iron absorption. I have also consumed a lot of raw cabbage for a few days for ulcers and read that it can hinder vitamin B12 absorption. It has been over one or two weeks now since I stopped by this pressure, but it seems to come and go. Or do I need vitamin B12 supplements to kick start?

I get nausea at times. Ulcer started when I was taking Aspirin for angina. I have been off Aspirin and with no angina for two months or so now. But it has only been a few weeks since I quit the PPI. The ulcers and angina therapy had me seating (leaning on my back and head) for several days and wonder if some neck or back muscle got hurt and now causes the head pressure and left lower neck tension.

Or could it be that my heart state declined into congested heart failure after the angina case? And now not supplying enough blood to the brain? The oxygen meter saturation meter shows 96-98%, though. I have noticed that I seem to struggle to breathe properly at night (sleep apnea perhaps) and wonder if this could be when the brain starves of oxygen. Kindly advise.

Thank you doctor,

Duly noted and will follow the same.