What do I do for strained ab muscles?

Stretch the sore muscles. Take a deep breath (and hold it in) and puff out your belly, then grab hold of something and lean backwards by rounding your back as much as you can, until you feel a stretching sensation in your abs. It should be a pleasant sensation.
This should alleviate some of the soreness right away, though it won’t make it go away altogether.

And in general to combat sore muscles, eat foods with potassium, like bananas. (Ideally you should have had one right after mowing, but it might still help.)

If it’s really getting in your way, I suppose painkillers should help too, yeah.

I had a couple bananas, they helped with some of the pressure. Thanks!

Anytime! :)

Be careful in that you may have done something worse like a groin pull or to me what you describe could be a hernia as well. That is exactly what my hernia felt like and if it is still painful 24 hours later or worse go see a doc ASAP.

@Cruiser Roger that! Thanks. I hope it isn’t a hernia. I just started to pay off my last emergency room visit.

I agree with @Fyrius and @Cruiser – both excellent advice. Gentle stretching helps relieve some of the soreness. (If you do take an over-the-counter medication, try an NSAID, like ibuprofen or naproxen sodium.) Also, try alternating heat and ice for a while, and if one seems more effective, you can just stick with it. If you don’t see any improvement within a couple days (I say “couple” because it often gets worse the next day) contact your doctor. If the dull pain changes quality (ie, to a stabbing or sharp) or simply gets overwhelming, call your doctor sooner.