I would expect a Mars/sun theme to show up in some way. Mars is drive, passion, aggression, rage, desire, will... all of those things... and sun is core sense of self. If transiting Mars is in Leo, home of the sun, we've got some extra emphasis on sun here.
I haven't noticed this so much with Mars square Mars, but when I have a Mars return, I get more impatient and short tempered, less likely to take any sh!t (real or perceived!). A few months ago, I had a Mars return at the very moment of the very day when the moon was opposing my natal Mars, and I really felt it.
For you, Mars isn't just squaring your natal Mars, it's also squaring your ascendant. That makes it extra powerful right there. And since natal Mars is on your ascendant, and domiciled, too, it's extra, extra powerful. Moon is currently in that part of the zodiac, too--Sagittarius at this moment, went through Scorpio a couple days ago--so your feelings may be extra on edge.
Mars square the ascendant, or itself, or any crucial point, could be an extra impetus to get going and make some change, or get something done. If there's something you've been meaning to do, this may be the moment you get around to doing it. If there's something you want to change about your life, this might be when you're more apt to take initiative and make it happen. However, it might be a small thing, and you might not know what effect it has until much later on.
Every Mars transit happens once every two years, give or take a couple months. The best way for you to know what happens to you during this transit is to pay attention to your experiences, and to also note what happened for you during previous times when Mars transited this spot. Get an ephemeris, note when Mars was here before, and anything you can remember about that time.