<p>Shutter shock is when the shutter mechinism causes a small amount of vibration during exposure and caused pictures to be a little less sharp. It's been talked about quite a bit on the dpreview site, with wildly different opinions. People seem to report it more with the E-M1, and at shutter speeds between 1/50 and 1/250 of a second. Also seems to depend on the lens.</p>
<p>I didn't think my E-M1 had the problem. But after the electronic first curtain option was added, I could see there is a small improvement in the sharpness. I don't think they added the feature to the E-M5.</p>
<p>As far as your indoor pictures go, there could be several reasons why they don't look so good. Maybe shutter speed, subject movement, auto focus missed. Hard to say without seeing one and knowing more details. </p>