Healthy Weight Gain

Hey guys! The last four months I've been training for a half marathon which I completed last week. Since then I've weighed my lowest at 91 pounds. I'm currently 93 (was 95 but lost two I think due to anxiety from ending a friendship, having someone important to me ghost me, and college being mostly virtual and having a tough time keeping up.) I'm 23 and am 5'1/4". My goal weight is 98 pounds. I'm not not eating. I can eat what I consider a lot (1800-2000 calories is a lot for me. I usually eat between 1400 and 1600 but I know that's not a lot for an athlete.) I've been a bit more relaxed about seeing numbers because I know I'm trying to gain weight. However being over 96 stresses me out and I still worry a bit about gaining too much weight. I used to be 105-107 and my mom would say something about my weight which always bugged me but I'm glad she did because I feel like I'm eating a lot healthier (I know I am.) Running is important to me as it is my time to be out of the house and it's my way of challenging myself. And I really enjoy it. Any suggestions to a healthy weight gain?