See a good doc is probably the best advice one can give to medical questions on Fluther..
That said, I’ve had something that is perhaps similar. My tongue would swell after certain meals and would feel like it was rubbing abraisvely on my back teeth (sometimes perhaps accompanied by a strange metallic flavour..). In other cases small point sources of irritation would come up often towards the tip of the tongue. I understand that symptoms like these might be caused in some cases by a flare up of Candida albican fungus or an overly dry mouth.
The closest thing I could find when I went a chasing for a diagnosis, was a loose congolomerate of conditions jointly referred to as burning tongue (or mouth) syndrome.
http://www.yourdentistryguide.com/burning-mouth/
Anyways, like you, I noticed a pattern that seemed to be assocaited with diet. First, my tongue got irritated with overly acidic foods. Pineapple or acidic dressings would cause discomfort. (this might be a separate issue from the one below)
In addition, a somewhat different type of swelling (primarily towards teh back and edges of the tongue…with imapcts on the gums) seemed to be associated with my eating yoghurt. So I cut down on that and started drinking larger amounts of water, avoided overtly acidic foods, and I started rinsing my mouth regularly with water over a few days following the symptoms. I also floss more now…which dropped the gingivitis…which dropped the irritation, which means now I have shinny white teeth and healthy gums (cue sparkly grin to camera….KACHING!)
This could be a coincidence…ie perhaps the symtoms would have gone away regardless, or only one of these factors helped the condition (ie more water). But this approach worked for me (no acidic foods, no yoghurt, lots of water, even better oral hygiene), and it also has stopped the sympoms in their tracks on the rare occassions when it came back in the months following the first outbreak (It hasn’t come back for over a year now).
So, as far as any relatively harmless anecdote is worth trying, I’d see what sounds relevant from my experiences and give it a go.
best of luck. (happy to clarify further if you think it’ll help)...