Hello Doc. Every Time I Press My Penis A Small

Hello doc.
Every time i press my penis a small drop sticky fluids comes out as i know sperm is white colour but the drop which comes out its colourless. And some times i loosee my sperm without mastubration even if i don't dream or think about any fantasy sex or like that..... please help.me. if it is serious proble suggest me medicine please.for this act i'll be very thankful tou you.....