Getting drunk

I am not a drinker, and besides this time I only drank like this a year on my gfs birthday and got the same results. My birthday was yesterday and my gf insisted we drink and get drunk. I’m 6’1 and weigh about 155. We finished about half a small bottle of patron and she was feeling but I wasn’t. I don’t like drinking because I don’t like the taste, but whatever she pouring I was throwing it back. She asked how come I don’t feel and I said I don’t know. She isn’t a drinker herself but has done it more than me. Any opinions on why this is. She’s shorter than me but weighs slightly more also.