Mercury is not a substance that will kill you. However it does diffuse through your skin due to osmosis. In reasonable quantities, mercury can damage your central nervous system. Do not continue touching or ingesting mercury. Unfortunately there is no way to remove it, there is a constant system buildup. If your contact was minimal you should be alright. Do consult a doctor if you are worried, but as I said minimal contact is relatively harmless. Be careful in the future of substances you are unfamiliar with.