I am afraid, its my 10 year old cat..?

I have had a cat for a long time, he is 10 now. He is a indoor/outside cat. he sometimes hunts animals.. :( sorry animals.. And lately i have been thinking he is prety old, and afraid he might p on. You see, I jus had a cat a couple months ago for 2 weeks and then he died, he was about the best cat ever... he would jump in your lap and snuggle and everything. And since then, im afraid of losing him. So, what im trying to say is, should i worry about that yet, or is it a bit too early for a 10 year old cat??