Sometimes in flying 'less is more'. Hypertension will definitely lower your ability to learn and your ability to perform. Your instructor is there to teach you and adjust their techniques to your learning style. If they can't, they should think of possibly swapping themselves with a different instructor.
I think most people (to one extent or another) will have suffered something similar. The process of learning isn't always a steady and constant progression so you shouldn't expect it to be. As you wisely note, you have recognised parallels between your experiences earlier in your training and now. Try and examine how you conquered your fears back then. It might just be that you very acutely recognise your lack of capacity and that makes you panic. Most of us don't even have the capacity to recognise our lack of capacity as we blissfully but confidently do something stupid. Remember that blissful confidence is far more dangerous than perceived incompetence in a flying environment!
Talk to people about your fears. If you don't feel comfortable with your instructor maybe a more senior instructor will be able to assist. I can guarantee that you won't be the first person in this position and you definitely won't be the last. Too often in this industry there is the pseudo pyscho b*ll*cks to man up and pretend everything is ok and act confident otherwise it scares the troops etc. Pretending to be confident is stupid.
The ability to project ahead comes naturally when your comfortable. Thus your capacity grows to consider potential threats. Capacity, unfortunately cannot be purchased, downloaded, copied or assumed. It's just something that comes.
Good luck, keep trying, keep your head up and don't beat yourself up so much!
