It could be bigger but it also doesn't look bad. The light makes it a bit hard to get a good look at the leaf color, but the growth seems to be coming up nice.

Does the soil you are using have amendments in it? Some brands do and you don't need to feed for awhile but others don't have much and at this stage the plant may be needing a half dose of nutrients to keep the momentum going.

If you have been overwatering and the oxygen levels in the soil are low, that is something that can hold back the growth a little in the early stages of growth.