Heeheehee, sounds like you need to be more grounded then Starry? No only joking, some people don't like the feeling of reiki especially if they have issues that need to be sorted or if they have a health problem that reacts badly. Next time start slowly, and just before Gassho rub your palms together fast a few times then shake away the energy then start, try keeping a few more inches away until you understand your strength and power, sounds like you are just a bit unbalanced and too powerful sometimes

2 & 3 will help with that as will practise.