Oh OP, that sounds like a horrible experience 💔 pretty sure I’d have reacted a lot like you! Sending a huge hug.
I disagree that 2 is too young to understand biting hurts. My DD was 2 in March & she absolutely understands biting hurts! She has been known to occasionally bite & I have always made sure it’s a firm no, that hurts mummy. She’s too young to fully get that she mustn’t do it again but her eyes fill with tears when I get cross & she rubs my shoulder & says mummy hurt, sorry mummy 💔
Having worked in nurseries, some kids are far more prone to violent outbursts than others. They will always have tantrums but you can work on how you will react & deal with this phase ( it will get better!)..
I would sit down with your husband and work on a plan you are happy with. Make a plan of how you approach tantrums in public. It may be something like taking a deep breath & just waiting for it to be over. I’ve sat on the floor in Sainsburys before while DD has gone bonkers. I was dying of embarrassment inside but I just kept quietly talking too her and offering her other options. 15 minutes later, she snapped out of it.. felt like 300 hours though 😫 but another mum came up to me & said she was so impressed I stayed so calm .. if only she knew how I was feeling!
Or if that just doesn’t work for you, maybe small things like working out how to anticipate an incoming meltdown & quickly acting to prevent it. Use whatever works, chocolate, crisps, a magazine, sweets 🙈 anything to keep the peace while you are out!
And any further extreme violence like today (extreme for a toddler), a consistent approach. Try to remain calm (hard I know), physically remove him from you if possible. Or at worse, pick him up like a rugby ball & get to your car, house, a safe space ASAP and sort it out where you feel more comfortable. And when he’s calm, you explain very firmly that he really hurt mummy & made her very sad. You would like him not to do that again.
I really hope you are OK OP. Don’t worry about your neighbours, if they’ve got kids, they’ve all been there! And if they haven’t, well, who cares! When you next see them, just be honest & open that his behaviour shocked you and thank them for helping 🧡