I may be wrong.. but I am the sort that hates question after question.. small talk fine, but if it isn't flowing, and seems pressed I feel frustrated. I also have ADHD, but I do tend to hyper focus on things I like... and if someone breaks that, I get irritated... not with the person, more the circumstance... and if she was in her zone with her game, when she's trying to focus on it.. during her break.. she may have given short answers so she could get back to her game. I HATE it when people bother me at the gym.. especially during cardio, when I have my headphones in I'm looking straight and someone decides they want to poke me for attention.. I try to give short answers too because I just want to get through my cardio and get even more aggravated when they are not picking up on my short answers. Even my husband knows not to come down to the basement when he heard me on the elliptical.. So my guess is, if she's a gaming freak .. when the game is out .. It's not a great time till after she is done.
Two things to try..
1. If you see her just wave hello and pass.. let her come to you. Girls hate it when the friendly guy suddenly doesn't seem interested. Even if they don't want to date them.. It's an ego thing.
2. If she's playing her game next time.. just say hey and leave it at that. When she's done say 'Hey, didn't want to bother you during your game.. . ___start convo here '
See if she says 'you don't bother me' or 'thank you'. If she thanks you.. her shortness was just her being in the zone.
Good luck. Oh and.. crushes at work are fun.. ex boyfriends/girlfriends are not..