Dizziness, Lethargy, Vertigo, Side Effects Of BP Medication Coversyl ?

Hi, I have been on medication for BP for about 12 months. Initially a one month trial of Coversyl 5. Once it was deemed this was the correct medication I went on to the generic “Perindopril 4” and felt relatively good for 7 months until I realised that it wasn’t treating my BP at all when I did a home BP test. With my GP we then started a trial and error process of various drugs none of which helped. We also did full blood test , stool etc. All of which is fine. After a couple of months of trials we have gone full circle and my GP has said try Coversyl 5 (my original trial medication) and come see me in 2-months. Now this is my problem. I feel terrible. I wake up every morning after 8, 9 , or even 10 hours sleep and feel crap. I am mildly dizzy and vague. I get a dizzy feeling if I shut my eyes. This mostly dissipates after a couple of hours but I still don’t feel well balanced. I feel generally lethargic throughout the day and get very tired in the evenings. I am 42, 186 cm, 87 kg, Exercise regularly and have never smoked . I have read about the possible side effects of Coversyl which lists dizziness , vertigo , lethargy which is leading me to the conclusion that it is the medication making me feel this way. Your comments would be greatly appreciated.