I put up an online community not to long ago and was thinking of joining Google Adsense. The problem i have is it says, i must be 18. Im 17 now and 3 months away from turning 18. should i worry? Should i still sign up?

No. Its illegal otherwise and youd be breaking the law.
You should either 1) wait til your 18 or 2) use someone elses adsense and share the revenue until you are 18 and can have your own.

Does your site generate a lot of traffic with a good CTR anyway?
unless it does yr pretty much wasting your time with ads.
Why spam yr pages with ads for if there not working and just putting yr visitors off?

Why not just wait the 3 months. You really aren't going to missing out on that much money in the meantime. Spend the time building up your community and then ad AdSense when you turn 18.

Yeah. Why don't you just wait for 3 months? In 3monts time, do other things while waiting for your adsense registration. Like building links, getting good content, etc.

When you signup on google adsense you will put your birthdate and they will know that your still 17 yrs old. So just wait my friend. meanwhile if you already have website or blog start the link building so that after 3 months you already have visitors and clicks on your ads.