The photos on this site of the permanent bumps caused by elastics are examples from my hair. It really is 100% permanent, and brushing out the ends and restarting are the only way to get rid of them.
If you are only wearing your hair in a ponytail to eat, you should be fine. The problems arise when you pull it tightly back for a majority of the day. As long as you are wearing your hair down for most of the day and you try to vary the height of the pony tail, you should be fine. Especially since you haven’t developed any “baby bumps,” I wouldn’t worry!