Everyone has different pain levels. Mostly teenagers are the ones with little pain, because they are still made of rubber. At your age, your pain will probably be equal or greater than mine. The best I can describe the pain is that it feels like someone took a metal bat and hit your legs repeatedly. That's what it felt like day-to-day even with the pain meds. Once the pain meds wear off, and they wear off sooner than you're allowed to take more, then it feels like you had a large open wound on your leg and someone took two hands and started ripping your leg apart.
That's what it felt like the first two weeks of lengthening. The 5-day hospital stint is bearable, because they give you powerful pain meds. After that, they get stingy on the pain meds. For the rest of your lengthening period, the pain levels vary depending on your ability to adapt to the lengthening.
I personally don't think it's worth it. If you had a lot of money lying around and it isn't going to go anywhere anyways, then it's probably on par.
And it also depends on how much you dislike your height. Is it a "that'll be nice to have" type of feeling? If so, it's not worth it. Is it a "I hate being stuck in this body shape and I get depressed thinking about it" type of feeling? If so, then it's probably on par.
The reason why I say it's "on par" is because you're trading off a lot for it.