So I uploaded a few things recently and only noticed till after I uploaded them that I submitted the wrong sized images.

Is there a way to fix it or do I have to resubmit them?

SirusStarseeker said:
So I uploaded a few things recently and only noticed till after I uploaded them that I submitted the wrong sized images.

Is there a way to fix it or do I have to resubmit them?

They need to be resubmitted. The image that a post points at cannot be changed or modified in any way.

Set the parent id to the corrected post id on the inferior post and then flag the inferior version. That way favorites and such will be copied over.