iPad password won't work

my iPad2 password not working problem is causing me serious stress. I have a number of imovie trailers I have made that are not backed up which I need to recover. my problem started when suddenly on Sat I noticed my iPad password lock was not required on my iPad. To protect my iPad ftom unintended eyes I went in and believed I set the iPad to require a password if it was left for two minutes. It is possible in my has I dud sone thing else. At the time my iPad was working on my home wifi. At about this same time I thought I turned on the keychain to share my password and twicd entered a 4 pin code ( same code as I used on my iPad!!! I then took my iPad to the office on Sunday and believe it would have automatically hooked up to my office wifi But not 100% sure. It also had a SIM card with data which I refently put into my iPad. I tried every password combination but got looked out for 1 min then 5 minutes. I was then told to put my iPad in recovery mode which I did then hooked up yo my iPad. Itunes would not let me sync my iPad. I am more sure if I have synced this iPad to my iTunes account but it is the PC I set it up on. While in recovery mode I updated from ios7 to ios8. My iPad is still locked out. It now says Slide to update but I cannot go further because my old password does not work. I am at a loss. Will pay for help. i live in Auckland New Zealand. Royally screwed if I can't recover my imovie efforts at least! Is there any IOS genius that knows a work around. It isy ipaf2, I also have my Apple ID and password, I also have my iCloud account and a 4 number pin I think for my key chain but not 100 percent sure. Big Mess! Part explanation for my meds is I am 67 and I IT guy moved out of time and is no longer available to me. Anybody Thanis Inadvance