I’ve been working on TSS, and despite counting very carefully my count is off by the time I finish the 2-3 “rows”
I made sure to count the one on the hook, that I picked up the correct number of loops ( previous row count is correct) and placing a stitch marker in the last stitch to make sure I don’t miss it.
I don’t see how else yo ensure correct stitch counts.
Did you accidentally drop the stitch at the end of the row?
Nope!
I don’t know… at that point I might just sneak in an extra loop somewhere 
The only thing I can think of is count while you crochet for a bit. Maybe one of the stitches is tight and you miss it periodically making the count off. That would make your row underneath because all the bars are there and correct but your current row wrong. It’s tight enough to not be noticeable as you go because everything else is so even. And happens so rarely because you are a consistent stitcher.
Is your count after the 2nd row lesser or greater than the chain?
Lesser
The best way is to count the loops on the hook. When you do the chain, chain one more than required, you can just leave the last chain loop off if it’s extra - just tie it up, it won’t be noticeable. So if you need a chain of 20, do 21, loop on the hook, count the loops. 20? Great! Q19? Use the extra one at the end to loop through another loop and make it 20. Now, when you do the reverse row, the first loop is crocheted by itself, just one loop in the first loop, as in the picture. Do the reverse row, then loop again, count. If you have 20, great. If less - look at the row, somewhere there will be 2 loops crocheted together. Ideally there must be parallel vertical lines forming a waffle pattern. See whether some lines come together - that’s where the reduction comes through, unravel up to that point and redo. Let me know how it goes
