On the bar that says xxx kb/ xxx kb used, what does it say is your maximum?
TP will have to decide how to fix this (either give you more room, or decide to delete your images, OR ban you for excessive picture use, his choice

).
I don't seem to have a way to search for all posts (only with attachements) by user, where I could go through your attachements to give you some more space till TP is on again.
If you want to go back (start at the oldest preferably) and find a few images that were attached that you think are not critacal to the thread, I will delete them for you to hold you over for a few days
EDIT: even though TP put on the thumbnail setting, I think you still get the full size of the large image taken away from your total, so while it looks like it is not a big deal to attach that 5 MB picture, it will eat up all your allotted space really quick.