My kids were never "normal" when it can to sleep patterns as babies. They still aren't. I tried all the suggestions for building a sleep routine. It never worked for either of them. My daughter especially was a horrible sleeper at anytime of day or night. At daycar during the week she would nap fine. On the weekends, we had to,put her in the car seat, drive around town for an hour, and then leave her in the car seat to get her to nap for maybe 30 minutes. She was exhausting! My son would fall asleep 5 minutes from home every day. As soon as I took him out of the car he would wake up. That 5 minute nap was all he needed to recharge his batteries and he'd be up until midnight. Even if he hadn't taken a nap the whole rest of the day. I thought I'd never get to sleep again!
I wouldn't worry about it. When he is older you can try to sleep train. But don't beat yourself up if he doesn't respond to sleep training. Now at 6 and 8 my kids are pretty good sleepers. But they still are night owls. They go to bed an hour or two after all their friends do. Sigh.