Well done on giving up both alcohol and cigarettes. t's not unusual for the cravings to hit kind of hard a few weeks or even months after quitting, so don't feel like you're doing something wrong.
The cravings will pass and eventually subside, but when the cravings come, I've found it helpful to remind myself that they are temporary, and that although they are uncomfortable, they won't hurt me.
You may also want to use a mental technique called urge surfing. It has worked for me: http://choosehelp.com/topics/recovery/cravings-mindfulness-urge-surfing