Really worried after heart operation

I was ill for a while last year and in the end collapsed and had a heart stent fitted .The surgeon told me it was a sucess and he had managed to repair the bad blockage but there was still a small one they tried to but could not get to to fix ..I felt so much better (sorry this was 6 mnths ago now) I could breathe and managed to start walking my dog again my knee went bad timing as it put a stop to getting fitter awaiting op for that ive stopped smoking never had one since my op and cut back on all my fat following all the advice given .
found the drugs hard to get used to and the last month the pins and needles and the pain in my chest is coming back but worse i do trust my doctor but hes adjusting my bisoprolol to help but it does not seem to be helping since he upped it again last week the pain is spreading across my chest and getting worse. Dont feel I can go back to him as he said it takes a month for tablets to adjust but the pain is worse than it has been .
I thought when i had the operation if i followed all the advice i could get better and fitter to help but dont know if i can keep on putting up with pain daily could not sleep last night it was so bad dont know who i can talk to for advice .