Rate of gain advice

Im 20F, 44kg, 177cm. I’ve been technically underweight for all of my life due to low appetite and also I’ve always played sports. Starting college, I was hit with the freshman 15 and noticed I was slightly fatter than I’d normally maintained, but didn’t give it much mind because I’d always let my body do its thing and be whatever weight that aligned with my lifestyle at the time. About a year ago, I lost what I assume to be about 35lbs (based on photos as I never used to weigh myself, but know what I look like at 125 and so I’m estimating I was probably around 135-140) in very short time span due to what I can only describe as an ocd/anxiety (not body image, important) induced crash diet after learning what a calorie was for the first time in my life. I ate about <1000 calories a day and tried to burn as many as I possibly could through cardio. This ultimately got me down to about 100lb, and I “reverse dieted” (began eating more) and think I developed hyper metabolism for a second and fell to an alarming low of 94.5lbs, which quickly corrected itself due to a combination of increased calories, strength training, and the effects of creatine which I had started taking 2~ weeks before this point. I began to eat around 2200-2300 calories a day, in combination with inexperienced and definitely ineffective strength training, which brought me up to about 100-101lbs, and I was gaining a lot of strength very quickly. I then had to go home from college for break and started a waitressing job where I was getting 20k+ steps a day, could only do calisthenics, and I began losing/barely maintaining weight again. Upon returning to college where I have access to a proper gym, I was about 99lbs which I have maintained for the past 3 or so months, not really fluctuating more than 1lb or so. I eat 2600 calories a day, and have started losing weight and strength on that so Im raising to about 2800 as per the guidelines of a lean bulk protocol. I eat about 170g protein a day, 340 carbs, and 80 fats. I’m aware I’m overeating protein, but I like protein a lot and don’t really fall squarely into any metric considering my height and weight, I don’t intentionally try to hit any macros, this just generally aligns with the meals I like to eat. I follow a ppl split where I prioritize compound lifts. I believe I am surprisingly strong for my size, I squat 115 for 5, deadlift 135 for 5, can only bench 55 for 8-11, and can do about 40 pushups in a row. I know that I am severely underweight and need to gain. Period. I am incredibly sensitive and reactive to deficits and surpluses, and I can tell that I’ve been in a deficit for the past couple weeks, but I find it psychologically very challenging to eat more, despite my best efforts. The last time I missed a meal (my catch-all weight gainer yogurt bowl that I make at the end of the day so that I hit my calorie target), it sent me into a deficit-induced spiral that led to make a string of monumentally terrible decisions. My goal weight is about 115-120 which is where I’ve sat comfortably for most of my life while eating and exercising completely intuitively. This weight seems insurmountable considering I haven’t even been able to put on even 1lb in the past 3 months of consistent effort. I don’t know my exact bf%, but i have striations, very visible abs, and crazy vascularity so I’m guessing it’s very low, definitely below the safe range for women. I know I’d probably be better off just eating like 5000 calories a day, but I’m deterred by the negative health implications of putting on weight that quickly. I’m not sure what to do considering most bulking protocols only suggest about 0.25-0.5lb a week on the high side at that. I have so much weight to gain that it feels impossible. I think I am coming to terms with the fact that this is just going to have to be a slow process and not something that I can fix in even a year’s time.

TLDR- I lost a ton of weight from an eating disorder and now feel stuck at a severely underweight 99-100lb with an insurmountable goal of gaining 20lbs cleanly and safely