Have you ruled out any tummy troubles-something new he's eaten, constipation? Teething can take forever, as mentioned, and my dd is also a bear when she teeths. He may be getting ready to hit a new milestone, and his frustration from the lack of doing so yet can come through as whining as he has no other means to communicate.
Also, a few minutes of TV time is no harm if it gives you both a break. You need you're time as well, and short nappers don't give you much Y time, do they?
For teething relieve without the worry of overmedicating, try Hyland's Teething Tablets. They're 100% natural, and if it's not teething pain, they won't hurt him to have anyway. At least that way you can rule it out. When my dd teets, she gets them before every sleep and during play time as needed.