I was wondering if this is just me or should I be seeing this?
Maybe I need to turn something off?
You have Auditing turned on. This can be useful in a Development system if you ever need to revert back to an older version, however, as you can see, if can create a lot of records.
If you want to turn it off, go to Tailoring - Audit - Turn Auditing On/Off - uncheck "do you want to keep backups of Changes"