Our cat ate boric acid?

Last night, our cat consumed some of the boric acid that we had put on the side of a door to keep the roaches out. We are pretty sure she only ate a small bit of it. Today, she is acting completely unusual and out of chahracter, hissing and growling when touched certain places or in certain ways, that normally doesn't bother her! She has never acted like this before and we just wanted to know if you think it is serious or from the boric acid.