Bloated and extremely tired?

For the last couple of weeks I have been extremely bloated, have absolutely no energy, and also very tired. I have gone to the doctor but she just said I probably need more fiber and to eat better. (Also not pregnant!!). I already eat very clean, walk all day long at my job, and get more than enough sleep. It's really bringing me down now and I have no guidance on how to get rid of all of this????