Advice/guidance on losing last few pounds on small frame

Hello,

I am looking for help in losing the final four pounds to reach my goal weight. My weight loss began August 1st, 2017 where I started at 143 pounds. I have readjusted my goal three different times once each has been reached. My first weight goal was 120 pounds, then 110, now it is 100. I am currently at 104 pounds and as expected, the loss has been incredibly slow but now seems to have completely stalled. For approximately 6 months, I followed the 1200 calorie goal set by MFP which I felt was fair for my height of 5'0. I recently readjusted my goal for a .5 pound/week loss as I had fewer pounds to lose and I was beginning to feel drastically hungrier than I had earlier in my weight loss. My daily calorie intake was increased to 1310 using the MFP suggested amount. Even though the increase was small, the extra 110 calories a day has been incredible. With this calorie setting, I also work out 5-6 days a week running 3-4 miles each day and have incorporated two days of weight training to begin building/maintaining muscle.

My problem now is in my current plateau-or what I hope is just a plateau. I am embarrassed to admit that it took me longer to realize that I should be eating back some of my cardio workout calories. After looking back on the past three months, I have been only netting around 900-1000 calories each week (and on most days). I realize now that this is not healthy and obviously the reason why I have been so famished these last few months as my activity increased. I have tried recently to eat up to my 1310 allowance but have still been cautious about dipping into the workout calories at this point. Even with such a huge deficit, I have not seen much of a weight loss. Since December, my loss was around 3 pounds per month, and now in the past two weeks I have not lost even an ounce. I have a food scale and weigh absolutely everything meticulously--no measuring cups or estimations. I am worried that at this 1310 calorie level my body is no longer able to lose weight. To add to my confusion, in preparation for maintenance mode, I have looked at several calculators to predict what my maintenance calories would be and they have varied widely—some saying around 1400-1700 while some have said 1300. These same calculators also state that in order to lose weight I should be eating between 1000-1100 calories a day. While I have been under this amount, I do not believe this is healthy or sustainable, even for a smaller person such as myself. I would not be able to continue with my level of exercise if my calories were reduced further.

I have given all of this information because I am worried that I am unable to lose any more weight unless I dig a deeper deficit. I am far too hungry to stay at 1200 calories anymore. I am trying to stay patient and wait longer to see if this is just a new normal (even slower) pace, but I am also reading too much conflicting information and am working myself up.

For my height and weight, is 1310 calories too high for a weight loss even with consistent exercise?

Thank you so much in advance for sticking through this long post and for all of your help.