When was the last time you intentionally disconnected with all that is happening around you? Had a quite time for yourself? Spent it on observing what is going on in between your ears? Could have been a while? No wonder you are constantly busy, even while you seem to be resting.
Meditation is tough. It needs lots of consistent work. To almost all of us, it does not come naturally. If you think rewiring you mind is easy, think again. But the best thing you are doing is trying. Any small amount of work is better than no work. It will all lead to improvement.
Occasional racing of thoughts is normal. The point that you are aware that of it is splendid. Instead of trying to control your thoughts, use the same attention to control your breath and you will get see amazing results in a short span of time..
There could multiple things that could be preventing you from being still. But that is not the point. Point is to still sit. Every day, for the same amount of time, at the same time, no matter where you are or what you are doing.