Crazy Cravings

I am 35 weeks and 3 days today and I've noticed since about week 33 I have been having craving thoughts for cigarettes and alcohol. I'd like to reassure I have not drank or smoked cigarettes in a year and do not plan to do so whatsoever until the baby is here if at all but I cannot help feeling like this is such an odd thing to want so bad during pregnancy. Has anybody else had this or something similar? Or maybe has an explanation for such behavior. I'd love to hear!