IQ is the mearing of how good your brain is on completing different tasks, mostly logic thinking(wich is different for everyone). So even if you have 60 wich is below "normal" it doesent tell you how smart you are in genaral.
I've done several tests, but no real IQ test(wich is expensive as someone mentioned) i have gotten scores between 86-116 wich i interprit, that i am "normal".