I might have an eating disorder.

(Tw for other mentions of poor mental health and SH scars) Hi, I (15 F) think I have an eating disorder. I haven't been eating lately, I've been eating under the recommended amount (I'm trying to stay within rules) by atleast 100. I've been excessively drinking water so I don't feel hungry, and I'm currently locked in my room so I make sure I don't eat anything till later. My sister did try to convince me to eat, but i lied and said i ate earlier. I've also been considering taking laxatives so the calories don't count and I hate throwing up. I did lose weight though, so now I feel like I can't stop now, especially since my doctor said I was healthy, and my mom said I look less bloated. Tbh, im overweight and I have PCOS which causes me to gain weight like crazy, and some serious mental health issues that makes it impossible to get out of bed most days. Plus, starving causes your metabolism to get low, so if I eat ill gain the pounds right back up. I want to be skinny by this summer, im going on a trip to a beach and I want to be pretty for it. I'm covered in scars from SH, which dosent rlly help with my self esteem, and I'm not attractive whatsoever. My stomach genuinly hurts and the water in my house tastes weird, so idk what to do. I've noticed I've gotten weaker, I can barely walk up the stairs without my legs shaking, but I think I'm just fat tbh. Srry if this seems jumbled, im genuinly rlly tired.