How long should it take to make a decision?

How long should I wait before I decide on a certain career/future for college and my life?

I was told by many counselors and teachers after high school, go straight into college. I did do some core classes, and then stopped and started working full-time since then.

After some time passed I went back and talked to a academic advisor and after we talked I decided to put if off a little more.She told me very specifically to be careful you do not go into something unsure and waste a lot of time,money and effort.

Now the year has come and is already passing….Yet I still truly have no clue what to do.And because of previous right knee injuries (ACL and meniscus damage) I stand a good chance of not getting into any military it seems.

I feel very pressured to do something but the more I try and figure it out the more I feel clueless and unsure.I do not particularly excel and/or not good at any subjects math,science or English.

What do you suggest in my situation?
Do I keep waiting and hope it just figures itself out?