2 Year old boy: speech delay

Just wanted to vent and maybe get some insight to any other moms that can relate. My son is 2. He says single words and understands me, but he doesn’t put together sentences yet.

I just feel like a failure that he isn’t up to the standard as some of the other kids in his classroom.

Any other moms have boys who had speech delay? When did they start talking more?! I’m trying not to be too hard on myself right now, but I feel awful.