Super Splendor electric start 2006 model.

From the past 2-3 days brake light is behaving weirdly, when pressed brake light the pilot light (small light beside headlight) , and speedometer console lights also lights up. Yesterday while driving back home i observed headlight is not too bright, and when i stopped the bike and pressed brake found that if headlight switch is on and brake light is pressed headlight also lights up along with pilot and speedo light,

i googled for such problem in internet and found that it might be sometime due to simple bulb problem of filament crossing or some earthing problem i am too worried regarding this, today morning planning to change bulb and see, i have spare bulb with me , tail light bulb, if this works good else please suggest me what to do, is HH authorized service centre the recommended place, will they do only needfull or just recommend changing whole electrical system, because thats for what authorized service centres are famous for,, please do suggest me coz from yesterday night only front brake light switch is working back foot brake light switch seems dead ;(