Permanent damage from long-term Prozac usage???

Hi - I stopped taking Prozac just over a year ago after taking it for 10 years at 20mg a day.  I stopped because I didn't want to be on it all my life.  Since stopping it I haven't experienced depression, *but* have been chronically ill for much of the last year.  My symptoms are Chronic Fatigue-type , with IBS symptoms.  I look unwell and feel like I'll never come out of this.  I have read a lot about possible permanent damage I may have done to my brain and also of the implications for my enteric nervous system.  Is going back on the drug my only route to feeling well again?  This is what my GP advises, though I feel she knows way less about the implications than I do, given our discussions.  I am a single parent of a 2 year-old and work full-time - I really cannot afford to be ill like this.  Any input gratefully received.

Thanks

Boborags