Do you often show up to work late? Are you seen as generally unreliable? (Be honest with yourself.)
Do you procrastinate a lot?
Do you have a hard time transitioning? Are you late for things because you a) can't accurately estimate time and b) can't pull yourself away from the thing you're doing at that moment even though you know you're going to be late if you don't?
Do you have a very unstructured sleep schedule?
Do you have high impulsivity? Spending (sounds like it)? Speeding? Substance abuse - including alcohol?
Did you breeze through HS with decent grades without trying but then suddenly find college and its unstructured environment and lack of supervision much harder and hard for you to succeed in?
If you answer yes to many of those questions, then you may want to talk to a psychiatrist about the potential for you being ADHD.
I was very much the same way and was diagnosed at age 29. Best thing to happen to me. I've managed to turn my career and my personal life around.
Everything you describe sounds like the impulsive behavior of ADHD to me, but I am not a medical professional and I am not trying to diagnose you. You just sound an awful lot like I once did.
Best of luck..