After a rough course of antibiotics for a sinus infection, my gut went sideways and — the part nobody warned me about — so did my head. Flat mood, brain fog, short fuse. Reduced diversity after antibiotics is well documented, and the gut-brain literature made the fog feel less crazy. I spent eight weeks deliberately rebuilding: a multi-strain probiotic, a prebiotic fiber to feed things, and a lot of different plants. I tracked mood and 'clarity' daily. Recovery wasn't linear — good days and slumps — but the trend line pulled up steadily, and by week seven the fog had lifted. Watching the graph climb was oddly reassuring on the bad days.