hello all. my first post in the forum and my first go at 5:2 this week. woo hoo! how exciting!

i was hoping some of you could help me out with some math…

i’m 26 years old
5 feet, 5 inches
155 lbs. (11 st. 1 lb.)
BMR: 1444 (according to the calculator on this web site)
TDEE: 1733 (this is a sedentary lifestyle setting; right now, i’m not exercising due to a terrible cold i’ve caught last weekend)

i’m mainly on this eating plan for weight loss purposes. but i’m also hoping it’ll be a gateway to giving me a different perspective on food. i’m hoping to reach 118 lbs. (8 st. 6 lbs.) SOMEDAY but i’ll honestly be overjoyed when i see 139 on the scale. for right now, i have my heart set to try to lose as much weight as i can (within reason) by christmas eve. or at least there being a visual change by then.

so my question is, how many calories should i be eating on my non-dieting days if i want to achieve such weight loss? or should i be eating less than 500 calories on my fasting days as well? should i add a fasting day? is it even possible to lose weight quickly at my height and weight without doing something unhealthy?? is there anyone who wanted to lose around 20-30 lbs. who wasn’t even that overweight to begin with? i do plan to start exercising 2-3 times a week by next week when my cold has passed so the TDEE may change but i like to plan for the worst lol.

thank you in advance!