How much fill do you have? Do you think you are at a good level or have you considered that you might be a little too tight? On days that you can eat, is it a normal band-size portion without being uncomfortable? Sorry for all the questions, just trying to get a better picture.
I do have the same issues. My band has been on "lockdown" as I like to say for several days in a row now. I have started to think it is tied to a number of issues: hormones, stress, band fill, and who knows what else. It can be very frustrating. Some days, like today, I can not eat a single thing and even liquids don't seem to go down correctly. It's counterproductive for me because I reach for things that go down easily during those times, things that aren't the healthiest, and thus I don't lose weight even though I haven't really "eaten" that much. (nice run-on sentence there!) And then just as I'm getting ready to see the doc about getting an adjustment, I'll have a good week.
If you find any official explanations, please share. In the meantime, I think I'm going back to the doc and have a discussion with them. I'm frustrated enough to spend the self-pay price of $200 for a slight unfill.