The condom broke and my girlfriend is pregnant?

last month the condom broke but we took a test and she got her period we did not think she was. but now she is late and took a another test and she is pregnant .from last month to now she went out abut tree times to a bar with Friends and drank got a little drunk all tree times if she was pregnant the first time is there a Chance that from drinking that the baby might of been damaged.