you're fine! play at your own pace.
When i finally dedicated a character to finishing the MQ i beat it at around level 25. i wasn't even 30 yet, and i was playing on master difficulty. so if you're concerned that it's going to get extremely hard, i assure you, its doable.
have you done any of the side quest? im on my 3rd play. doing all the side quest before i do the main quest.
"Spoilers!? In the general discussion!?"
The player is too overpowered so you could probably beat him at level 10. Also he scales (I think).
theres over 200 hours of quests alone.
there are radiant quests (reoccurring quests)
if you ever just want to get straight into some action, go to an inn and ask if there's any work to be done
then there's the DLC
not to mention giving yourself quests (EX: if your character has a a bad history with trolls, and you consider yourself a troll hunter, then go around and find some trolls to kill)
what im saying is that its pretty hard to lose interest
the first time on