Tourist visa extension

I'm from the United States and I planned a 5 week Indonesia trip. I incorrectly assumed that the Visa process to extend over 30 days would be easy but now it looks like it's a real hassle. Is this something I can do myself or do I need to hire an agent?

I'm really mad at myself because I'll only be staying an additional 5 days past the 30.

How much of a hassle is this? Thanks for your help.