Sleeping longer and oversleeping can seem like it would make you feel more rested however yes you can be more tired as a result of oversleeping just like getting too little sleep can make you feel really tired.
To feel rested during the next day you need to go to sleep at the same time every night and then wake up at the same time in the morning.
This is so that your body is used to the sleeping and waking time so that you get the proper amount of sleep.
When you go to sleep at different times then your body doesn't really know when it's actually time to go to sleep so you can be awake and not actually sleep as good at night.
Then you sleep in more the next day to try and catch up on sleep and when you do you usually feel even more tired.
Oversleeping also influences the expression of cytokines in your body which is a reason you feel more tired after oversleeping.