Very sharp back pain after barbell rows?

[Bill Bailey]

I was doing barbell rows and felt a tear in my back, now that was an hour ago and I can't barely do anything because of the pain in my back. I'm even hunched over to the left typin this. The pain is just under my left shoulder blade. Any diagnosis would be helpful thanks
Thanks I hope it is just muscle spasm, if so how long will it take to go away?