Is This Karma?

Wikipedia defines karma in the following way:

Karma (Sanskrit: कर्म kárma (help·info), kárman- "act, action, performance"[1]; Pali: kamma) is the concept of "action" or "deed" in Indian religions understood as that which causes the entire cycle of cause and effect (i.e., the cycle called saṃsāra) originating in ancient India and treated in Hindu, Jain, Sikh and Buddhist philosophies.

I can't help but wonder if certain things that happen to me are the result of karma. It is no secret that I give my husband a hard time..........a really hard time more often than not. I love to pick at and aggravate him..........he does the same to me......it's just how our loving relationship works. Yesterday though, I think he got me back for a lot of my picking and aggravating...........he ran over my foot with the back tire of a go kart. He swears it was accidental. He was so upset about it that I do believe him. I now have two toes that are swollen and one that I am fairly sure is broken. Is this karma? Do I need to let up on my hubby some?

What are your thoughts on karma?