I was playing a match and a sova was defusing and I check the spike and he wasn't there but then I got shot right where the spike was. Everyone watching me didn't see him too.

I am a low sensi player and after playing for 2 hours ,my hand hurts (a little bit). As a result I become inconsistent. Can anyone suggest me how to overcome this besides changing my sensi ? Is there any exercise I should do before hopping...