Atenolol Leonard S Lilly, Pathophysiology of Heart Disease, 50mg Tablets, Informative Book, Internet Check

I have been taking atenolol for about eight years,25mg daily.I was never titrated to find out what was the correct dosage! This used to regularly done in the seventies to patients going on to this and other similar drugs. About four months back the pharmacist supplied me with 50mg tablets (clearly marked as such on the box and on the tablet), I did not notice the mistake.
However after about a month of dreadful nightmares,falling out of bed etc., I checked the tablets ! The pharmacist was very apologetic..
About two months back I started to have almost continual headaches/dizziness. I reduced the atenolol by cutting the tablets in half, after ten days I stopped taking atenolol.
I have been carefully graphing my BP and it has risen from an average of 140/80 to 160/88. This for three days with out atenolol.
The headaches ae now minor and respond to paracetamol=tylenol in USA.
I am now taking indapimide 1,25mg daily to see if this will lower the systolic. If one needs an informative book buy: Pathophysiology of Heart Disease by Leonard.S.Lilly
Also on the internet check Vaughn's Summaries very informative.