(so sorry!) TDEE question

UNLESS19

Ok so my weight loss has slowed down. i'm on 1,200 cal as my daily goal (which sometimes i struggle with.. i don't know why.. it may be as i'm too scared to snack or indulge in case i have no cals for my evening snack)

So basically i went on a site to calculate my TDEE just to see (using http://iifym.com/tdee-calculator/). I put down my exercise as 6 times a week, as everyday i'll try to burn at LEAST 200 cal with a workout DVD or walking etc. I left one day free in case i didn't burn much or had a day where i need a rest/feel discouraged, which isn't too often. To my surprise it's only (rounded down to the nearest 100)
TDEE -25% = 1, 300
TDEE -20% = 1, 400

Should i use my TDEE? Go from -25% then to -20% (as eating more than 1,200 worries/scares me, so i want to ease into it- i don't want to gain!!) How much should i net? I don't really want to eat back what i've burnt. How much should i try to burn & have i calculated it right using 6 times a week for workouts?

Thanks so much! & Sorry for adding to the mass of TDEE questions haha!