So I got in my 2001 X5 3.0i and came to work this morning with no problems. Come lunch time, I go out to start it and just got 2 clicks... but no start. I finally got a jump and it started but its sounding like hell, it sounds rattely and just very rough. Also besides sounding terrible, it has the brake light, the abs light, and the triangular light illuminated on the dash. So my question is, what do you all think it may be? Im thinkin battery. But has anyone else experienced this and what did you do.
Please help ASAP!

Thanks
-Ryon