The Battle with Naptime

Is it normal that my toddler doesn't want to take a nap anymore?

When he was about 4 months old, I did sleep training with Coqui, so he would fall asleep on his own. And after about a month (or more) he finally succeeded. I also trained him NOT to fall asleep in the car, but to wait 'til we get home.... Well, that kind of backfired NOW, that he never falls asleep in the car, ever, no matter what time it is! Oh well....

But he used to take great naps. I mean, we would go out in the morning, come home, eat lunch, and go to sleep. No problem. Then, about 2 months ago, when it started....
He would lay in his bed, and would not fall asleep, even after an hour or so. But at least, he stayed where he was: in his bed! That changed though, after a month. Now he comes out every 5 minutes and asks when he his quiet time is over.... that is not relaxing to him, nor to me! So I tried to do quiet time with him, while the baby sleeps, kind of like a special treat, because now he has to share me with Peanut.... Well, that worked for about a week, until I got exhausted, because I did not get a break at all....

Any suggestions? Like on how to make him rest, so he is not falling over his dinner plate. And how I can rest, too.....

Other than that, Peanut takes great naps.... that does help though!