K.L.
Hi S.,
I recommend buying the book "The Way I Feel" and starting to discuss different emotions with your child, it sounds like it's time. The problem is that frustration is such a hard thing to deal with, especially when you don't even know what it is, let alone appropriate ways to deal with it! With my now 26-month old girl, we talked about stomping our feet and "roaring like dinosaurs" when we get angry, rather than hitting, kicking or biting. Or when frustrated, letting "the tickle bug" make us feel better. The message needs to be not only that certain "easier" reactions are bad, but that there are safe, appropriate ways to express those feelings and get them out, without hurting someone or something else. That's the key. I also allow my daughter to hit her stuffed frog chair in her bedroom (but only that) if she truly feels she is so frustrated that nothing else will help. This way, you provide a way to validate her feelings, which is great, without condoning actions that are hurtful and disrespectful. She barely ever even hits that frog anymore! But she also tells me when she's angry or frustrated now, too. It seemed to help her so much to "name" the feelings and understand that they were temporary and would pass. Toddlers are learning so much and have so many boundaries, it's very normal to get frustrated, heck, adults do it every single day. The trick is to have healthy ways to express ALL our feelings, not only the positives ones we like to have.
Good luck!
K.