Did I download spyware?

So, I was checking my email on my android phone earlier and opened an email from “USAA”. I don’t have a USAA account, I knew it was a scam, I opened it just to block the sender. As soon as I opened the email though, I got a message from my phone that said “download complete”. I did not click the attachment, I have no idea why my phone downloaded anything, all I did was open the email! I immediately checked my download folder, there was nothing suspicious there. Ran Avast and Malwarebytes, but they found nothing. I can’t figure out if anything actually downloaded or not. Is it possible to download an attachment just by opening an email? Should I be worried that my phone is infected with something?

can you enter you mail account from a computer using webmail?
if the mail contain a attachment, download and save it to your computer (dont run it) then upload and scan the attachment here www.virustotal.com
if scanned before, click rescan for a fresh result and post link to scan result here