I have a question, I'm hoping someone can answer. I've been on the blood pressure medication HCTZ...

Hi. I haven't been on that particular medication, but it does sound like an allergic reaction. Which, yes, is a bit strange after this length of time. But something else could be going on. Do you keep an eye on your blood pressure at home? It's invaluable to have your own machine. And it also means you can regularly give your readings to your Doctor, which will go in your notes.
I, also, have high blood pressure, and take 2 different drugs for it. I, have to regularly give my readings to my GP. Recently, my medication had to be increased as I felt very unwell. And I spoke to my GP on the phone, she said I sounded very confused at the time and she called an Ambulance. They did all my observations and they were okay, apart from very high blood pressure. They spoke to my GP as I said, due to covid, I am not going to hospital!! Once she increased my medications, I was okay. So, there are other drugs your Doctor can prescribe. Don't forget to report these side effects. There are details to do that in the patient leaflet that come with your medication. Have you checked in that to see if it lists these symtoms you have, as a side effect?? I hope you get sorted.