Hoppy, are you completely emptying your bladder when you say that you wet yourself, are you finding that pads don't quite catch everything?
I only ask because you really ought to be able to go out confident that pads will keep your clothes dry. I know that you may feel embarassed, but honestly, loads of women have problems with stress incontinence.
Seriously, try the pads for the moment and try and get help from a physio as mentioned above.
I use always's envive pads because I find them much lighter than tena ones, though if you are losing a lot of fluid, something more substantial might be the way to go. My bladder control was never brilliant (I had 'accidents' as a teenager) but I started wearing pads whilst I was very overweight. I found that as I lost weight I didn't really need them (except for when I had a cold - sneezes - eek). But when I became pregnant it came back, with particuarly bad accidents during morning sickness.
Please don't allow this to affect your day to day activities, a combination of pads that fit you well and some physio should help keep things more manageable.
Take care of yourself, you are definately not alone.