Welcome to the Forum, sdm06. Nervousness doesn't seem to be part of the side effects of Metformin although no one can rule out how it may affect different people. Here is a link for its side effects:
http://metforminsideeffectsinfo.org/ You can try Googling the side effects of the BP meds you're taking too to see if it might be them. There may be certain factors to consider like taking the meds separately or taking them with food. If the nervousness continues, speak to your doctor as well as your pharmacist. A pharmacist may be able to see if it's the combination of meds. Sorry you're having this problem.