Icloud Data Mixed With Someone Else's

A while ago i lost my iphone over the side of my boat. I needed something for work so i borrowed my mothers iPad. I logged out of her iCloud account on the Ipad (at least i thought i did) and logged into mine.

After i got my new phone in the mail i restored the new phone from my iCloud backup. All of my contacts, messages and apps were restored. However my pictures (that were backed up to my iCloud account) were deleted and replaced with the pictures from her account. Also her stored passwords were transferred to my phone.

I had everything backed up to a computer as well so it wasnt as issue of loosing anything. This was about a year ago and i turned iCloud backup off to not deal with it. However i was to get everything working correctly now. Can i log into my iCloud account on a computer and delete all of the data somehow? (Basically make it a fresh account) And them sync my phone back up to iCloud to get my pictures, passwords etc on there?