Back again, need to get in shape for summer and my 40th

I joined MFP last year just after the New Year and had a pretty good 6 months (though it wasn't easy). I was training a lot, 6 days a week, sometimes twice a day and counting calories as well as macros, trying out several ways of eating like low calorie, then high calorie, then low carb plus 5:2 until I found what worked best.

I was finally getting somewhere and had managed to lose around 15 lbs and I was really enjoying my training but then I had an ear infection for a couple of weeks, followed by a fall which left me in A&E last July. I stopped watching my diet, stopped logging and stopped exercising, mainly because I was in too much pain. Luckily I wasn't too badly hurt but was left with a lot of back problems which still haven't really gone away and every time I think I'm better and try to train I end up in pain again.

I am now back to square one having regained all the weight I lost (plus a little extra body fat) am down to 0 training, except for a little walking. I now really need to sort things out as I'll be 40 in September and want to go on a special holiday to celebrate but only if I can get in shape before then as I don't want to feel uncomfortable and avoid the camera the entire time like I have done before when on holiday over the past few years. That paired with the fact that I can't face another miserable summer in the heat where I live, keeping myself covered up and being depressed about the fact that nothing fits me any more has made me want to do something about it more than ever.

It was hard enough last year but this year it's even harder as I can't do the things I could before, but really need to find a way to get my fitness back up and my diet back on track. I've got a new puppy and although she's small she does need to go on walks so that is my current motivation to get out at least for a few minutes every day and I'm going to start logging my calories again and following 5:2 as my mum has been doing really well on it for a year now and has given me a cook book to help.

Anyone have any other advice about what I could do? I have lots of fitness DVDs but don't want to do anything too strenuous and risk being in pain again with my back. I have been seeing a healer who thinks that from time to time I have a trapped nerve and also that one or two of my vertebrae are a little out of alignment but when I had an MRI at the hospital after my fall nothing showed up.

I don't want to overdo it but was thinking about attempting a bit of Yoga or Pilates and also some light weights on my arms and legs I've lost a lot of muscle tone, though last time I tried weights on my arms my back started hurting again.