Voice Change Finish Changing At 16 ?

I was 16 in January I'm 5 ,10 . I have lots of hair on my body and armpits but my facial hair started 5-6 months a go . I have moderate acne and I have to use Proactiv. My voice never cracked but got lower in time it started to change around 13-14 .... I'm a singer who sings a lot I train my voice with the (mastering mix program from Brett Manning) ...When i talk my voice doesn't crack but when i sing when i go around E4 it strains and crack a little ... I'm scared I'm not gonna be able to sing anymore because my voice will get to low and that I will be stuck singing Elvis lol ... IS IT STILL CHANGING IS IT GONNA GET A LOT DEEPER ... Help Please Tanks ... I love singing and i want to do it professionally !