Couple months ago my wife upgraded to a Galaxy S7, which came with a free GearVR. I've messed around with it a few times (and I do have glasses), but I experience the same as you. After a bit my head just kills me. It does have a focus knob, so I figured I'd try it without glasses. Seems ok, but I couldn't dial it in just right.
For what it is, though, it's a cool little thing. Once things mature more (and I get to a point where I could afford an upgrade that would run one), I'd love to get a Rift or a Vive.

On a side note, I'm kinda kicking myself for not getting Lasik years ago. At the time, there was a place in the area that was starting up, so what they did was work with our insurance to drop the cost to what insurance covered, making it no cost out of pocket. There were a few people at work who did it, and loved it. I was just way too hesitant though.
Fast forward to today, and it's just way out of my range. The insurance I have now essentially doesn't cover it at all.