I'll give you a general feel how it looks under my eyes usually.

If I get enough water and rest, I have very small bags under my eyes, basically unnoticable. If I dont get enough sleep or water, I tend to have bigger bags under my eyes. But recently I noticed something interesting. On one of the days where I had lots of water and a good nights rest, under my left eye I basically had no bag at all..on the right hand side however, I had one and fairly big at that. The interesting part is not that it was puffy on that side and not the other part, the interesting part is that it doesn't look puffy to me, it looks swelled up. (a bit red, but if you touch it, it seems swelled, its not soft as the other side is) When your eyes are puffy it comes out but if you put your fingers on it, it feels fairly soft.

So I am totally stumped what this could be. I was thinking along the lines of thyroid issues or kidney issues.

I am a 22yr old male, have had no other medical issues, and otherwise healthy. I dont take any medications.