Hi Accessory and welcome! Just wanted to say hello and offer a few thoughts...
I have often heard that becoming aware of a problem is the first step in solving it and given my own struggles and those whom I've worked with, I find that to be true. However, sometimes, due to low self esteem, depression, physical illness, addictions etc., our perception of something being "wrong" with us can in fact, NOT be true. So I guess I'm wondering a few things... has anyone actually TOLD you they think you have problems or are "different" in some way? If so, I think I'd first ask for examples so you can truly understand what they are saying. Then I'd ask myself "do they have an ulterior motive in telling me this?" I would then ask others that I trust and/or respect their opinion whether they have noticed anything troubling or unusual about you lately. Finally, I'd schedule both a physical AND an appointment with a therapist if I continued feeling that something just isn't right. Above all, trust your gut! I know that can be hard to do when we are hurting or confused about something but if you are feeling depressed, sad etc., that is your mind's way of saying "hey, something needs attention over here" --much like a bleeding wound indicates a bandaid or even a few stitches may be needed!
I think it's great that at such a young age you are being proactive and reaching out when you are hurting. It took me a longer time (as did going to college lol) but I got through it and I know you will too!