When i'm on or around my period i tend to get bad food cravings then i indulge, how can i prevent myself from blowing my weight loss plan?

Needs planning: Diet plays a crucial role in the management of PMS. The best way to curb PMS cravings is to raise levels of serotonin in the brain. This can be done by eating carbohydrate-rich foods in combinations with a protein source like beans, lentils, chickpeas or lean protein like chicken or turkey. Try planning your meals. Try getting rid of your periods altogether with OCP. Exercise.

Specific patterns: need specific recommendations. It is good you've identified the problem as cravings. Underlying it are internal cues (emotional, needing something in hand or in mouth), external cues (how food looks) and of course ingrained habits. http://www.amazon.com/dp/0692496157/ specifically addresses many different patterns with individual solutions, and general behavior methods. humorously.