The whole thing seems odd.
Because this pit bull came running and jumping at me and the only thing I could do was to do a shin block to defend the attack ... I would off ripped my arm off if it got my wrist. so if a dog is attacking you block it with you shin and keep hands away from its mouth.
Not sure how you did all that thinking in the instant the dog was running up to you. Seems like a lot of thinking.
My guess it was more along the lines of: "Big dog! Stay back! <Kick>"
the thing that saved me was lucky for me I had a Ice coffee(a milk coffee drink in Australia)that I was throwing over its head, if I not had that it would of killed me
I don't follow that logic. I imagine a small drink as useless. He probably wouldn't notice anything. Unless you had a big container, say 20 L, the drink won't do anything more than mildly annoy the dog. And if you had a 20 L container you could have used it to start bashing the dog, which would probably only cause it to bite harder.
One reason I now need a weapon.
Really? How frequently are you attacked?
Of that is one reason, are there other reasons you need a weapon that weren't part of the story? Like you were planning on going skeet shooting next week?
A better response would be to talk to police officers along with your photos and doctor bills. If the person doesn't immediately agree to pay all the medical bills and other costs you incur, then you start considering legal action. Weapon-buying usually isn't a step in that process.
Then today I went to the doctor to get a tetanus shot
Ah, the infamous rusty dog tooth.
If you were due for a tetanus booster shot (or you don't have records of them) that is a good reason by itself. It is more likely you were due for one of those and they happened to have you in the office, so it was a great time to give you the shot. It takes several weeks for the vaccine to take effect, so it is good for your next puncture, not this one.
the doctor gave me a script to take to the chemist, after showing my leg to the chemist she said lets go back to the doctor and then there was a shot, shot of some thing
Most people figure out what it is they are being injected with, and if it was an immunization, people keep immunization records.
I'd suggest you figure out what those injections were, figure out what the prescriptions are for, and what the charges are going to be so you can get them to the dog owner, along with the police reports of the event.