OK SO basically I got an email from a "FEDEX agent" that I idiotically opened on a school computer (my teacher disconnected and fixed the computer thankfully, and was nice about it, it's just that I was waiting on a parcel that never arrived and the carrier was coincidentally FEDEX, but I still feel like a moron) and it was a virus that continuously prompts you to disable windows account control and security when you open the attached file no matter how many times you say no. (It did not link me to a particular website.)
At the time I had a USB connected to that computer to work on my projects. I plugged it into my laptop in order to scan and quarantine it; nothing was found by mcafee or malwarebytes so I uploaded all of the non-installation files and formatted the USB. Then I sent the email to the FEDEX abuse email and deleted it.
Nothing has been hacked and no personal information has been leaked as far as I am aware. However, ever since that day I keep getting a random popup prompt on my laptop that appears in the blink of an eye every few hours and disappears before I can see what it says or do anything.
I have found nothing out of the ordinary from my list of installed programs or my task manager, and mcafee and malwarebytes also don't see anything out of the ordinary. Should I be worried about this, or let it go?