since its a lenovo, it could be their recovery partition. DId you originally clone the HDD that it came with to the SSD?
No, i just deleted the Windows partition and installed Ubuntu instead. Now i did the opposite, and are left with 1 mb unallocated space at the beginning and end of the HDD, as well as 7,79 GB of unused space. In UEFI it says that I have 2 Ubuntu partitions, but I guess the smartest thing would be to leave it alone, as it is just ocd-like tendencies that makes me want to overwrite the unallocated space