Palpitations are very common in the menopause and most women will experience them at some point. I do know from experience just how horrible they can be (mine came at night just as I tried to get to sleep!).
The menopause tends to stress the body's stress system (the adrenals) and this makes the adrenals extra jumpy and responsive to any kind of stress, physical or emotional, and this in turn then triggers the palpitations. It is importation to support the adrenals so taking a magnesium supplement and a good female multivit should help, daily relaxation is vital and can help symptoms really quickly.
Low blood sugar and dehydration could be a factor as well so make sure that you eat little and often - have healthy snacks, not sugary ones, more protein/carb based such as plain yogurt, nuts and seeds, oatcake and cheese etc and make sure that you are drinking plenty of plain water during the day. Try to avoid caffeine if possible, if you really need one have in the morning only, as this can be one of the main contributory factors! Acupuncture can often help with this so worth looking into as well. However, if these continue or get worse it is important to get them checked out by the doctor as well.