If you have a scale then start monitoring it's weight just so you can see that it is not losing too much. Most times they won't lose more then about 10% even on a long fast, depending on the size of the snake. Obviously if the animal is only a couple hundred grams, then it has less to lose and that can be more problematic. We had one go 110 days last year and towards the end it was down about 12% in total weight.
It's impossible to know the sex without probing or popping. That being said, you should have someone with experience do it for you so as not to injure the snake.
You can try and offer food every two weeks until he/she starts back up. That way you aren't just getting tons of refusals. Don't forget you can refreeze prey items once, but after that pitch it. As long as all your husbandry is correct, it will just start back up whenever its ready and there probably won't be much rhyme or reason as to why. Welcome to the wonderful world of ball pythons.