Hey there,
I'm sorry that you're struggling. Regardless of whether or not you have a diagnosis, struggling with a condition that is inherently isolating can be extremely detrimental to anyone over time. As others have suggested, it really is important that you get yourself referred to an ED clinic and get help.
I was diagnosed with anorexia at the age of 13 and I'm 23 this year, and I recently sat for (hopefully) my final A-level retake. Although my ed has more to do with childhood trauma than body image, it definitely goes hand in hand with my maladaptive perfectionism, perpetuating a destructive cycle of 'failure'/relapse fueled by the academic expectations I have for myself. After 10 years of being in and out of hospitals and rehab, missing school, and losing friends who grew busy actually living—I can tell you that the validation/sympathy I initially received would diminish fairly quickly once my family and friends got sick of my antics. I'd subconsciously retaliate by getting worse; at the same time, I remained stubbornly ill even when I received love and support. Eating disorders are ruthless, contradictory and cruel that way.
That being said, you are not alone. Wherever you are, I'm sending you love and I feel for you. X