sleep

So is it wrong that I love to sleep? I came home from work today at 12 like I usually do and had lunch. Nothing special so far, but then I took a book from my bookshelf and lay down to read. I got an average amount of sleep last night and have not had a particular strenuous week. But as I lay down to read I got tired and said oh well I will just have a quick little nap. 2 hours later I woke up, I looked at the clock and thought just 5 more minutes, another 2 hours with me asleep. Then I wake again, and have to force myself out of bed, I swear I could have slept another week and a half. I dont understand why sometimes I can sleep forever and other times I will sleep like 4 hours at night and be rip roaring and ready to go. Is it the weather is it something wrong with my internal clock? I am really still very sleepy perhaps I will go lay down for another 5 minutes or so.