Confused: Eating the Correct Calories?

I am a 24 year old female. I currently weigh about 130 pounds. I am 5 feet 4.5 inches tall. Ideally, I would like to get down to 120 pounds, although this number isn't set in stone and I more just want to look slimmer. In the past, I have struggled with my appearance and had issues with eating. I think at my lowest weight I was around 105 pounds.

Fast forward to now, the restricting turned into severe restricting and then ultimately binging. I am really, really, really trying to go about all of this the healthy way and not revert to past behaviors. However, I am confused with the correct amount of calories. I have calculated my BMR as 1408 and the TDEE as 1682. This is with, obviously, no exercise. I am a full-time college student, and I do not get nearly enough exercise. I am trying to exercise 3 times a week (to start), and when I do that, I track the burned calories and work towards eating them back. But, right now, I have my calorie intake set at 1430 on days that I do not exercise. I did the TDEE -20%, but it put me under the BMR, so I changed it to -15%. Does this seem about right and healthy? I do not want to gain any more weight! I have tried the 1200 calorie thing in the past, and I lose a lot of weight doing that, but it also leads to me eventually severely restricting.