one of the most obvious advantages the germans had to me, was pilot quality. many of the german BoB pilots had served in the spanish civil war, were battle hardened, and had plenty of good quality training. british pilots in the height of the BoB had 7-9 hours flying time total before being chucked into combat, many of those hours were spent just learning how to fly, you had to pick up how to fight as you went along...
as for the blitz, what happened was that a german bombing raid accidentally dropped on civilian districts because they couldn't find their target. in response to this, the brits bombed berlin, with a small force, more a morale booster/breaker than an effective bomber raid, but it enraged hitler, and he moved away from attacking radar and airfield (which were nearly destroyed, another week and england would have been ready to invade), and ordered mass raid on london. the blitz was a cruel dishonourable tactic of a madman, but funnily enough, it saved britain, and gave us enough time to geather the airforce and mount a more coordinated and effective resistance.