Is my transplant ruined with cold water?

Hello! I have just had 1500 grafts placed and had my first wash at the hospital. The next day I had travelled back home and washed my hair. However the hot water wasn't working around 1 am (when I arrived home) and washed my head with quite a chilly wash. I'm worried incase the cold water has damaged my grafts. Everything was done carefully and gently... but it was cold :/