BMR/ CAL DEFICIT/ CAL INTAKE ETC ETC..

According to MFP's BMR calculator, your BMR is 1448 calories. This is the amount of calories your body burns just stay alive, with zero movement (ie, if you slept all day). To get your TDEE (Total Daily Energy Expenditure), multiply your BMR by 1.2 for a sedentary person, so 1448*1.2=1738. This is how many calories you burn just going about your life, assuming you are sedentary. You would need to eat 1738 calories a day for maintenance, to not lose any weight at all. So subtract 500 from your TDEE to get your daily recommended calories, 1738-500=1238. This is what you need to eat to lose 1 pound a week.

That was the math, now for some advice. You already don't weigh too much, so you probably don't have a lot to lose. This means that losing quickly might be more difficult for you than for someone who weighs a lot more. I would recommend changing your goal to 1/2 pound per week or else you might get discouraged because you may not be losing as quickly as you want. Also, I would have trouble getting full on only 1200 calories a day, however many people do just fine with that much, so you'll have to try it for a while to see how you feel. Keep in mind that MFP recommends that women don't below 1200 net calories for the day, or else you body probably won't get all the fuel and nutrients it needs, and you could end up feeling like crap and/or hitting a plateau further down the line.

You will also have to eat more on the days you exercise. Eating back your exercise calories is controversial on the MFP forums. Some people say to always eat them back, some say to never eat them back. I say, eat them back or not if you want, as long as your net calories for the day is over 1200. Also, in my calculations in the first paragraph I assumed you were sedentary, with a job where you sit all day. If you have a more active job/lifestyle you get to eat more calories.