frustrated and ready to give up

Don't give up!!! It sounds like you've made some great changes already and it could be anything that caused that 1lb gain. More importantly, how do you feel?? Do you feel better physically? mentally? Instead of fitday I use thedailyplate.com and they have EVERY food listed, I swear, LOL ,and be sure to log your exercise too!!!! Maybe check that out. Be sure to eat lots of dense protein and some good carbs to give you fuel for the kick boxing, get plenty of water in. Hang in there and keep doing all the good things you're doing~you CAN do this!!!!!!!

I find that journaling is the most important thing.  I hear that The Daily Plate has more items than Fitday, but I use Fitday.  I've spent years adding new items with nutritional info. to the list.  If I can't find the specific thing, I just guestimate. 

The thing that always baffles me is how fast those calories add up.  Journaling is the only thing that keeps me honest.