Giving up bad things when your pregnant?

Soo when I found out that I was pregnant I stopped everything bad for you .... Like bad food and coffee and pop.... I don't smoke or drink that much but anyways I was doing great till over the weekend I got a huge headache well I had a can of pop then a few more lol i know it's bad but yea I need to stop lol what is your "bad" thing you can't live with out