I do agree that only you are the one that can make your decision. Find yourself a gender therapist somewhere around you and go talk to them about how you're feeling. They are the only ones who can give you a recommendation to start your full transition. You're probably still young and trying to find things out and I know that it's very difficult. I never really knew who I was until I was 28. I didn't know about transitioning until I was in my early 20's. I did consider it a few times before but I wasn't exactly sure. I knew of a few people who transitioned and I saw that they seemed a lot happier. I was always uncomfortable with my genitals, I was always uncomfortable in public. I didn't like being labeled as a lesbian, I didn't like being called a "Dyke". I hated how people looked at me, it caused me a lot of anxiety and stress. My relationships were never good and I was never happy in them because I couldn't satisfy anyone or at least I felt that way.
When I first started packing and binding I started feeling a little bit better but not 100%. I was more stressed out that I was trying and I still got misgendered. I finally made an appointment with a gender therapist and I spoke with her for about a month or so. She took me out in public to see how people reacted to me and could see the many reasons why I struggled with myself. I am now 2 years on testosterone and about 2 months post op from my chest surgery. I can tell you that I personally feel 100 times better than I use to. My anxiety is slowly subsiding and I don't have any issues with people in public. It feels really good to be identified as "he,him, sir". I still have depression but I am learning to battle that on my own.
I am not telling you that transitioning is going to solve all of your problems. It is a life altering experience that takes a lot of time and thought. I'm not saying you are not transgender but there are guys who do it out of it being a "fad". There are some guys who stop taking testosterone because they don't want their hair to fall out, or they don't want to get fat. If you choose to do this you need to make sure this is really what you want. You will be giving yourself injections (or however your doctor choose to administer it) the rest of your life. You will be seeing a doctor every few months to have blood taken. Your emotions will change and you may even become much angrier at times. You may loose your ability to really have a good cry (I know I did).
Just make sure you educate yourself properly before going thru with this. Reading these forums does help a lot and you can always find some amazing people to give you answers. This transition should be for you and nobody else. As far as binders go there are a lot of websites that I'm sure will send them to you in the UK. You can check out GCB2, Underworks, Amazon (they have underworks), Man Sculpture. If you can't afford one there are also binder donation websites you can look into such as In a Bind. I also have a few binders I need to get rid of since I don't need them anymore. You can always send me a message and I can see if your measurements will work in one of mine. I'll send it free of charge

. Best of luck to you on your journey my broski!