Dealing with Hyper and Hypo Blood Pressure

I am Almost seven years out from a tumor base of my tongue..(squamous cell) I deal with all the problems I read about on the Discussion Boards as most do..They seem to just be a way of life for me and I deal with it..ie ... taste, no saliva, hard to swallow, etc..I still get my support at my Medical School but one I am still looking for help on is my Blood Pressure which can get very high even with BP Meds ex...220 over 120 and after I eat it will be 95 0ver 45..When this happens I get somewhat Weak Knees, Faintie,and a need to stand for a minute or so before i move ... Took me years to figure this out as i never monitored my blood pressure after I ate and it never has happened as often as it has been lately .. ..Now that I do.. My cardiologist has ruled out Post Prandial Hypotension and has referred me to a Kidney Doc..who i will see in December... My kidneys have checked out very good in the past .. My question is ..has any one else experienced this problem???
Thanks ...MJ