Is my trainer interested in me?!

Tonight, after she first noticed me, she stopped what she was doing and stood there looking at me, glanced, behind her, at the client she was with (who was putting something away) and then back at me, still just standing there amongst all the people. I kept my head forward and tilted down, but was looking at her out of the corner of my eyes. It was far away, so I'll assume she couldn't see where my pupils were directed. She kept trying to catch my eyes, tonight, it seems. She'd pass by, looking right at me, but I never looked back. She even brought her client to work somewhere near me at one point; I got self-conscious and moved.

She watches me a lot. Glances over at me in various areas throughout the gym. I've even seen her looking at my a**(while she was kneeling beside a client, I'd seen her in the mirror I was facing, behind me looking at my butt)

But when I am with her, she acts rude/bitter, especially when I first meet up with her. She doesn't smile and she doesn't respond to my playful tones. She used to, in the beginning. She was excessively flirty/friendly and I didn't really respond. I remember the second time I was with her, she wore perfume and had her hair primped a bit (she's my trainer and I notice now she always just has it in a pony, bun, or straight down & plain and I haven't smelled perfume since) and she kept trying to make me laugh.

Though, the very last time I was with her, she managed to start asking stuff about me. She was throwing questions at me (I'd been answering about all the places I've lived/moved and where I planned on living the next couple years so I guess she was interested in that)