Seedling grow stuck

From the look of your soil, I would say you're giving it far too much water.... this can drown a plant and kill it. You need to let the soil dry out completely before giving her another drink. Seedlings have very little root structure and thus are prone to either drowning or damping off if they stay too wet for too long... less is more when it comes to watering them at this stage! She actually looks to be fairly healthy so I don't think you've done her in - just let her breathe a bit and she should start to perk up and grow. Good luck!