Yes, you should look into renewing your passport. Sometimes, you can buy additional pages. I actually ran out of room while in South America, but it did not seem to bother Chile, Uruguay, or Argentina. They just flipped through, saw there was no room, and double stamped on a box. Then, it got a bit wild and started in the margins. Thankfully, I was able to get to the embassy and arrange a new passport. Which by the way, looks awful. The new US passports look and feel like they are made of cardboard, and I hate how they put the information one page into the book, rather than the first page. Now, I have to always flip through to get to the details. But I was pressing my luck. Go get a new passport.