Kristen,
Yes, there is a limit now and no it doesn't delete any pictures that were already in the gallery. Check and see if you are over the limit, I am sure that you are based just on the ones that I have looked at, and then decide if you want to delete a bunch to get back to the new limit or below it so you can load newer pictures. You can find out how much you have left or how much you are above by going to the Load Picture page and it will tell you how many bytes you have loaded. If you still have any space, there will be a sort of graph near the top and any green means that you have that much space left.
Edit to add picture. Here is a picture of my Image Upload Page:
Ron
