Irony?

I never really know what irony which is ironic in itself (or maybe just odd) cos I'm always complaining about people who use the word all the time to describe something else.

But I think this actually may be irony:

I was brushing Hamish's teeth the other night. As usual he was refusing. As usual a wrestle ensued. As usual i was explaining that teeth brushing is important if you want clean healthy teeth.

As I'm struggling to hold him I had the handle of his toothbrush in my mouth. He then bucked violently, his head hit the brush and it chipped one of my teeth.