Chest pain, Heaviness in chest .

Sir,my age is 50 yrs.and for 2-3 years facing problem of chest pain and heaviness in chest after walking for less than 0.5 kms or doing normal chores like carrying little weight or climbing few stairs with bag. Some times now getting this even during night while sleeping.This chest pain and heaviness in chest left me exhausted terribly and I have to completely freeze my actions if any.This pain then later recedes slowly after remaining in standstill position. While undergoing such problem I feel that I have walked or run 10 kms, heart beats increases and some sweat on face and head.This started some 3 yrs back but happen after doing some strenuous activity for some time. I am also having DM-II. Facing acute ED problems and also could not perform during sex due to heaviness and pain in chest.Some time I observe that this Chest pain or heavy breath, increase in heart rate/palpitation and heaviness get starts also in state of botheration or tension.This has completely stalled my life and I am unable to conduct physical work or walk or run or any exercises.Kindly suggest me medicine to overcome the above problems. Thank You