White patches and spots, muscle weakness

Hello Doctor, I have got one big white(discoloration) patch on one hand near thumb, similar but little less on my penis(outside). Have also got very small to medium white spots/lines in both hands mainly below elbow area.  Have attached pics covering major areas(including penis one). Please note that I first observed spots only in penis tip, and recently only since last 2-3 months I noticed in hands.I am also feeling very weak on both hand,leg muscles, morning stiffness. Pain comes in back on feet's heel too post wakeup in morning or while walking after sitting bit longer, but that started to come only after I started l walking after years gap. Please suggest which doctor to meet and what these symptoms might relate to. Thank you. I met one dermatologist and got white spots as vitiligo but don't understand other symptoms which are also developing in similar time as spots so concerned. I have been living sedentary life since more than 7-8 years, with minimal physical activity.