help?

I am a 32 yr old male.... very active and no previous medical issues.  Nine months ago, I felt as though i was having a heart attack (chest pain, shortness of breath, arm pain/fatique)  I have since had numerous MRI's, CAT scans and blood work, urine tests, I even had an angiogram.  Nothing seems to be showing up in the tests.  I am now having trouble with blood pressure.  At rest it will spike to crazy numbers a little while later it will be abnormally low.  I am trying medications to try and aid in the symptoms but have had no luck finding the problem.,.I also have extreme weakness in my arms when i do anything physical with them.   I have seen cardiologists, endocrinalogist and my own doctor.  I am hoping some ideas can be brought forward as we are all at our wits end trying to figure out what is going on.  I had a 24 hr blood pressure test and it shows exactly what I have been saying and yet, still no answers.  has anyone else had these symptyoms?