HELP! Sick seedling

So... my seedling is looking a little bit unhealthy, I still think she's going to grow just fine... just wondering what the issue could be.

The only visable issue I can see is the stem and leaves turning yellow, besides that things are going good...

Is this a nutrient problem... maybe fungus gnats? Tell me what you think:

Do none of you fuckers appreciate a good gag every once-and-a-while?