AITAH for being furious at Walmart after they talked my almost 85 yo parent into taking shingles, RSV, and pneumonia vaccine at the same time?

I have now gone all the way through terrified, furious, and out the other side, and now I genuinely can’t tell if I’m overreacting.
My parent is close to 85. Lives alone. I live more than a thousand miles away and I call every single day. I was just there for a week the beginning of August. Although they do well living alone, today, I would love for them to come live with me, have a live-in care giver, or move into assisted living.  (My plan is to move to Alabama when I become eligible for early retirement in 3 years.)
Yesterday they went to their local Walmart in Alabama for ONE shot: the shingles vaccine. One. They walked out having been talked into THREE: shingles, RSV, AND pneumonia. 😤 Because apparently the Alabama”Wal-Marks” pharmacist 🙄 asked if they wanted any other vaccines while they were there.  Like it was on some kind of special or something.
Cut to today. Full-on confusion. Delirium.
They turned their cell phone off last night and now have no idea where it is, so we are down to the landline. I have called that landline 42 times. TODAY. A whole lot of them back to back. And every call goes something like this:
They answer. We start talking. Mid-sentence - CLICK. Hung up. I call right back. They answer like I’m a brand-new mystery caller. “…Hello?” It’s ME. Again. Still me.
Then they set the phone DOWN. Not on the receiver: just… down. Usually about six inches in front of them. So now I’m hollering into a landline lying flat on a table, the mantle, the sofa: “KEEP THE PHONE IN YOUR HAND!!” Nothing. So I switch into full search-and-rescue mode and start SCREAMING “WALK TOWARD MY VOICE!!” at the top of my lungs.
“Look on the table.” My parent is at the kitchen sink. “WHERE ARE YOU NOW?!” Back on the sofa. Not looking for the phone. Just… resting. (Oh, we are looking for my phone?)
And yes — I thought about asking a neighbor to run over and check on them. But my parent “packs”, currently operating without full mental clearance, and I cannot in good conscience promise anyone’s safety over there right now.  So we are doing this by landline. 
They are okay. They will likely be back to themselves tomorrow, hopefully.  If not, I’m catching a flight tomorrow! 
Here’s where I might be the asshole:
I am LIVID at Walmart. My reasoning: the CDC does allow giving these shots together, and for a healthy 40-year-old who lives with other people, fine. Stack ‘em, and if you feel feverish and wiped out, somebody’s home. But my parent is close to 85 and lives ALONE. Those overlapping side effects - fever, aches, exhaustion, and confusion - hit completely differently when there’s no one there. And confusion is the one where the patient can’t follow the “call someone if you feel off” instructions, because they are the one who is off. Nobody at that counter asked if they live alone or if anyone could check on them. They just sent an 80-something home solo with three shots in them.
My family is split. Half of them are like “you’re overreacting, it’s normal to give vaccines together, the pharmacist didn’t do anything wrong.” The other half agree with me that you don’t load up a frail person who lives alone and send them out the door with zero questions asked.
So — AITAH for being this angry at Walmart for this? Am I wrong that they should’ve asked whether my parent lives alone before giving three at once given the KNOW RISK? Or am I just looking for someone to blame?