This is embarrassing, I did the same thing. I received the exact same emails you did. I also received a text message saying that the paypal activity was suspicious and to respond that I authorized it or not. I went to text response back to paypal but it told me that it had "expired." I emailed PC-tech to ask where it was shipping from and they did not respond. I did get an email on the 9th, one day after I put in the other and it said
There is a problem with your order and payment was marked as unverified. We noticed unusual activities on our PayPal so we advise you file a dispute right away. Dispute the payment now and let me know and i will inform you on what is the update.
Looking forward to your swift response.
I then saw your post and pretty much confirmed what I thought. I opened a dispute with paypal but they just requested more information. Not really sure how this will go down, I don't think they are legit and I am unsure what to tell paypal- wish they would tell me what more information they need, afterall they are a tech giant and looking into a spoof business should be pretty easy for them.