I Take Tab Tenormin (Atenolol) 25 Mg In Morning And

I take tab Tenormin (Atenolol) 25 mg in morning and half tab of 5 mg Sofvasc (Amlodipine Besylate) at night with half tab of Tenormin 25mg for last 5 years. My pulse rate was at that time 90 plus. I am diabetic ang Sulphgroup allergic.
Now I feel and also looks very weak. Allot of pain and weakness in my legs. These days I also notice twice or thrice miss pulse even I feel it in my left side of neck. Pulse rate is 72 per minute.
Should I change my drugs or add something else.
Thanks.