how many backups are stored in icloud

I recently deleted an exchange account from my prior employer, not realizing doing so was going to also delete contacts I thought were saved directly to my Iphone. In reading other posts, I reset my Iphone in order to attempt to restore the phone based on a prior backup done two weeks prior, before I deleted the exchange account. However, when I hit the "show all backups" option to restore my phone, it only gave me the two most recent backups performed today and yesterday. Is there a way to access and restore your phone to a backup performed two weeks ago? Please note that I did not ever back up my phone through Itunes/my Mac so Icloud is my only option. I do pay for extra Icloud storage. Thanks in advance.