Help!

We are on our second attempt potty training. I’ve read the oh crap potty training book or the 3 day method. My son will be 3 in February. He seems to have pee down pretty well, and has done a few poops in the potty, but keeps pooping his pants. I watch for the signs but it’s like in 2 seconds he’s already pooped himself while standing. He feels embarrassed too. Granted it’s only been almost a week, but I feel like he shouldn’t be having to many poops in his pants. Any tips for me? Anything is greatly appreciated!