I'm 22f. I've been losing weight for 105lbs in the last 12 months on a 1600 calorie diet. I have now gained 15lbs and I don't know what to do.

My weight loss journey was going great. I lost 105lbs and I got down to 280lbs. I ate 1600 calories a day. 40% carbs 40% protein 20% fat. I've been on this same diet for the last year. I never had to change it. I kept losing weight. I felt great. I was feeling less bloated. I was sleeping better. I was feeling stronger. I was feeling more energetic. I was feeling like I had a reason to live. I felt like I could finally be happy.<br><br>Then I started gaining weight. I tried my best to keep my diet and exercise routine exactly the same. But I kept gaining weight. I gained 15lbs in three months. I went from 280lbs to 295lbs. I don't know what to do. I'm so scared. I'm feeling so bloated. I have no energy. I feel weak. I feel disgusting. I feel like a complete failure. I don't know what to do. I'm so scared. I feel so lost. Please help.<br><br>Edit: I'm not sure what happened. I just woke up one morning and I had gained 7lbs. I thought it was just water weight but it never came off. I kept gaining weight so fast. I don't know what to do.<br><br>2nd Edit: I'm a little embarrassed that I accidentally posted in the wrong sub. I'm a little overwhelmed with all the comments but thank you so much for all the advice. I'm going to see my doctor next week. <br><br>3rd Edit: Thank you all for your advice it really helped. I saw my doctor today. My thyroid levels are a little low. She wants to see me again in two months and we will go from there. Thanks again.