Is it just me---or is there a real issue re the power dumping aspect of my nearly new Samsung 5?

Yeah, here we go gain. Many of you know about my issues with my Windows 8 or is it 8.1 or is it somewhere not quite 'either?' let's put that conundrum aside for a moment and introduce yet another 'Neil' issue with technology. My Samsung S% is only a few months old and it has developed this maddening quality whereby it suddenly 'dumps' the charge---it goes from about 45% charged to stuff-all. Yes, I understand about my Jack Russell and kids having hissy-fits but this is an extremely annoying quality that I would be most happy to have resolved! Am I doing something wrong? OH---it gets hot too and I don't understand that. For what has been labelled a quality phone, one would assume that issues should few and resolvable. If any of you kind readers of Roskill, my blogs and other utterings on FB have an idea---one that will forestall my proposed visit to Vodafone tomorrow, then bring it on. OK--I expect a few 'insensitive' remarks re my lack of knowledge about the described issues, but hey---give me credit for attempting to be part of this new, sometimes unkind 'techno world.' I do not wish to return to the world of 'smoke-signals' or using two cans connected by a long piece of string. www.authorneilcoleman.com