i can not erase my photos

I have been having some issues when i try to delete my photos from my ipad3 with the iOS5.1.1 and my phone 4s with iOS 7.0. that have got the same Icloud adress, and are sincronized. I go th the Photo app and select all the photos i want to delete,I think i have deleted them, but by the next morning when i go to check they All appear again. I have tried lots of things, i have pluged the ipad to the computer and tried to delete the photos from there, but they only appeared 200 photos when i really have got 1.800 photos.

The thing is i have no more memory in my storge and i need it, plus i also want to delete some old, miningless photos.

I would be thakfull for your help.

Thanks.