Since my brake job when I brake sometimes, it feels very soft, and my foot pedel goes all the way down. And sometimes at the red light, I feel my foot sink to the ground. Do i have air in the lines? does it need to be bleed? Job was done long time ago (6 months) but this just started.

 

yes you are exactly correct it has air in it and if the air comes under too much pressure it will turn to water and rust your caliper and make it stick so go ahead and change the brake fluid if its never been done but if it has then just bleed and refill with either dot 3 or dot 4