nitrous effects?

I received a filling today and my dentist gave me nitrous oxide as an anesthetic.  I've used this before at the dentist and have always found that the effects would ware off within minutes after the procedure.  This time, however, I recall that I must have been asleep or something, and I had two really strange dreams, which had never happened before.  I'd always stayed conscious while on the nitrous.  Almost an hour later I'm still feeling a bit of the effects.  I can't quite describe it.  I just feel a bit out of it and it's weird and frustrating because I can't shake it off.
I remember that about ten minutes before I went to the dentist I took two motrin for a headache and I'm wondering if that could cause some strange effects combined with nitrous and how long do you think this will last?  Could this be dangerous?  My headache is back and I feel nautious and very out of it.  It's extremely annoying.

[HelpinUtah]

I've never heard of any problems with mortin and nitrous causing problems.  I would call the dentist and ask him/her if it's normal.  Good luck!

[jst4shanell]

I have that happen to me every time I get nitrous.  It usually lasts all day for me.  I am nauseous and tired and really out of it.  Almost dream like.  I have never asked my dentist about it because I have had other people tell me it makes them feel the same way.  Hope this helps