TIFU by being honest about wanting to try something

*This was actually close to a year ago, but I didn't realize how much this tanked my self-esteem until recently.*

Background: I (30m) had been dating, let's call her Nina (29F) for going on six months when this happened. Things were going really well. We could spend hours lost in conversation with each other, had similar interests and life goals, and our personalities seemed to mesh really well. Nina was full-figured with a larger chest than ass. The sex wasn't mindblowing, but it can take a while for me to get used to a new partner. But we'd lay together in a sweaty tangle afterward and talk about heavier things: our hopes, traumas, dreams, and fears. The kind things a friend of mine poetically calls "that vulnerable type shit."

The Fuck-Up: Nina and I were getting hot and heavy one night. After probably an hour of kissing, teasing, and other pants-tightening action, she asks the fateful question: what do you want, baby? I've always been more of a boob guy and wanted to try titfucking. I never suggested it to anyone before because I felt kinda weird for being into that, and it doesn't seem like it'd do anything for the other person. But fool that I was in the moment, I was honest. Worst she could do is say no, right? Wrong. She starts laugh...really, really hard. Not a playful or teasing laugh; she's laughing like I just told the funniest joke she's ever heard. I'm mortified and can feel my face getting hot with embarrassment. I vaguely remember standing up and sort of leaning against something. The laughter continues for some time. I couldn't tell you how long it actually lasted, but if felt just shy of fucking eternity. As the shock of that reaction wears off and I regain some presence of mind, I hear her wheezing pretty badly. Shit. She's having an asthma attack. An asthma attack from laughing. An asthma attack from laughing AT ME. Nina's in no state to go grab it from her purse at this point, so I rush to the living room, dig through her purse, find the inhaler, and get it to her. I make sure she's alright and doesn't need to go to the hospital before quickly going home. We did not continue dating.

TL;DR: Was getting hot and steamy with a woman I was dating. She asked what I wanted, I said I wanted to try titfucking, she laughed so hard at me that it triggered an asthma attack, and I had to get her inhaler.