First of all, it might not come back, could've been a one-time thing that will go away completely if a break in training's taken.
If it does come back, it's likely a warning not to continue what is causing this, the high stress of deads. Personally i think heavy deads are dangerous, put a lot of pressure on the spine, muscles, etc. Very intense and stressful, can easily cause injury that can last weeks or months. I don't think it's necessary for good development.