Do I just have a high tolerance?

So i turned 21 in march, and im experimenting with all different types of drinks, i have tried vodka, rum, pucker, and now tequila. I am slightly frustrated because i have a very tough time getting drunk, the only time i could say i was drunk was when i did a TON of vodka. Well im not big on shots, my drink of choice is a margarita so far, i dont care if its gay its good, but i cant seem to get drunk off them, i have had 3 big glasses of margarita last night and didnt feel hardly anything, any advice on other potent drinks or ways to spice up my margarita?