Are afternoon naps a godsend, or do I just need sleep?

I don't tend to get much sleep on any given night, usually around 3 to 4 hours a night. I can mostly function like that, but by the afternoon I'm already close to passing out. Taking a nap in the afternoon can be refreshing, but waking up in the early evening is disorienting. It could also make it harder to actually sleep at night, which is a problem I don't need more help with. 

I've been trying to stop taking so many naps so late in the day, partially aided by some afternoon tea. I'm hoping that if I'm not napping, I'll be able to fall asleep earlier, and no longer feel so tired during the day. I'll post an update in a few days to let y'all know if I'm sleeping better or not!