How much would it take for me to get drunk on champagne?

If I've had dinner and everything, but am not used to drinking? I'm five foot nothing, and I weigh about 90 pounds, if that helps. I'm wondering because I was telling my girlfriend what a lightweight she was from getting tipsy one glass of champagne and one glass of wine on New Year's, because I remember once when I was eleven I had two glasses of champagne and was fine.