So after doing some research and jiggering with my budget I found a fitness centre quite close to home that has a PAYG option. I've worked out out that I can afford to do either one gym session or exercise class per week and so I booked and did my first gym session today!
I had my induction where the guy showed me the various machines and how to operate them and then he left me to it and then I managed 40 minutes of exercising before I felt the start of a panic attack and had to leave.
I didn't push myself too hard but by the end I was definitly sweaty and for most of it I had a bloody annoying wedgie that I didn't feel able to deal with as the place was fairly busy. I may have also made a daft comment to the inducting guy about not wanting to lose my boobs which I put down to nerves. 
I'm afraid I don't really have a question for the board but as I lack friends in the real world and I was proud of myself for actually doing something I just wanted to share it with someone.
Yay! 