Toddler Hitting Everyone/Everything

So my 2 year old has recently started hitting me, my husband, and any items whenever he's frustrated. He doesn't say very many words (to which we have our first speech therapy appointment in 2 weeks) so I know that's the main cause. My issue is that after he hits, he will immediately say "sorry" and hug us but then does the same thing 10 minutes later. He picked up the "sorry" thing at daycare, which I appreciate, but at the same time I'm trying to figure out the best way for him to understand that even though he says sorry, it doesn't mean he can do it again. Any advice? I try to talk to him after every time he does it, but it just doesn't seem to click just yet