Chronic fatigue after taking a course of antibiotics

I had a surgery a couple months back that went well with the exception of an infection that hit me 9 days after this. I was given a course of antibiotics to take for 2 weeks, flagyl and cipro. about 5 days into this I started having a number of concerning side effects: an increase in anxiety, balance issues, brain fog, of course heavy fatigue. I was told to continue this for the full time period to really eradicate the infection. Well, I got to day 9 and had to stop this because of the mentioned symptoms being so life altering. As I sit today (5 weeks since stopping this) I still have the unrelenting fatigue and brain fog. Really curious if anyone else out there has experienced this. My doctor and the surgeon say this will lessen over time, and to eat nutrient rich foods to rebalance my gut. But this is fatigue that I have never felt before, not relieved by adequate sleep. A heaviness to everything. I have adderall to take from my primary, but that only treats the symptom and not the cause. Really affecting my life right now in all facets.

I also cannot take antibiotics without having great problems...
I wonder if the fatigue is not there because of other parallel infections that develop due to antibiotic treatment, such as fungal infections in the gut?
Another possibility are viruses: they are unaffected by antibiotics, and as antibiotics wipe out the good bacteria that could be keeping your immune system in check, viruses that were dormant could wake up and cause fatigue.
My opinion...

You woke up something with the abx and are herxing from it. Its the dieoff of bacteria. This happens when treating lyme and other tic infections with antibotics.

Remember antibiotics do nothing to viruses, they kill bacteria only.

When taking ABX, you need to take probiotics (good gut bacteria) at the opposite time frame (so ABX wont kill the probiotics) , otherwise your setting yourself up for gut yeast overgrowth.

Yes, but good you reached out. It took me 15 months to get back to what I consider "normal" functioning pre surgery and anibiotics. But.....I went ahead and had stem cell therapy performed here in MN. I made this decision because I wanted my life back. I was at the brink.....many of my passions were based on being active, and being able to work close to FT. It was expensive, and took 5-6 months to really kick in, but it helped me soooo much in regaining my energy/sanity. Again, my CFS was all caused by flouroquinolone medication which is what I found out can do so much damage internally to your cellular energy process.

How did yours start in for you? That can tell a lot in regard to what to try. If virus induced, or in my case a certain medication, may dictate other ways to treat it. D Ribose and Creatine along with Lots of Mg and B12.

So this is recent. At fist glance you may have thrown your microbiome out of whack. Pro biotics and glutamine may do the trick for you. For me it was the telltale sign...post exertional fatigue that was so our of proportion with the activity I did. I exercise a lot, so know what my body is capable of. When I could only do a fraction of what I was used to, and having 2-3 days to recover I knew there was a hit to my ability to make energy at the cellular level. This is where the stem cell therapy helped out...to regenerate the damaged cells.