My napping is out of control!

I try to wake up around the same time everyday (usually 7am), but then I fall right back asleep and not wake up for another three hours! The same with my naps that I never plan on...I'll just be sitting in my Lay-Z Boy chair watching TV in the morning and then the next thing I know, I wake up four hours later. It's starting to become an everyday thing and I'm concerned because it's affecting my ability to sleep at night when I'm supposed to be asleep. What can I do??