Where to start.......? First, it's great to see someone with enthusiasm, that will get you a long way and is essential if you are to make anything out of photography, you will get some difficult times to need a positive outlook and lots of drive.
I wouldn't initially suggest taking someone else's photo from your site as you are probably breaking copyright which is really not a good thing to do
https://www.facebook.com/photo.php?fbid=3865683567577&set=oa.383345651710581&type=1&theater
I would also take a look at your photos on the page and keep the best and clear out the rest.
On to shooting the 2 weedings you have booked and possibly other shots you have lined up. First, are you registered with HMRC, you are taking payment, you need to be registered for tax. Also, as you are doing a professional job, make sure you have liability insurance as well as professional indemnity so you are protecting yourself in case of any problems.
Getting on to gear, when shooting a wedding if you can only afford to buy 1 body to start with then beg, borrow, rent a 2nd along for the big day. The same with any lenses that you can't cope with out and the flash. You will want to get enough memory so that you can get the shots and not run out. Depending on file size think 40Gb or more. Lastly, batteries, have enough and then a few more for the flash gun and also extras for the camera.
If I wanted a basic starting setup then I think the lowest I would be OK with is (based on Canon as I don't know the Nikon range well) 550D and Tamron or Sigma 17-50mm f2.8 and a Canon 430EX Flash. Sure, it is over budget, but this is still the budget end of things.
Having the kit is only just a really small portion of the game, you then need the camera skills. You are going the right way with shooting lots, I would say don't go with lots of different things, just work on a little aspect at a time. Learn about composition, learn about lighting (broad and naorrow) this is really key, work on people skills, this can be make or break to get the best out of a subject.
I think that has covered the very minimum of things. It was illuded to earlier I think in another post, about not going out and doing a bad job, it will really damage your rep. Only do a wedding, or any other important job, if you can do it well, if you are not 100% sure you will do so then leave it until you can. You don't want to have an unhappy bride and groom post wedding.