Hi,
Just wanted to get some advice about my car. Recently had an issue with my cambelt. The glow plug light came on while driving and so I turned the car off but it wouldn't start again, just turned over upon inspection it seemed the cambelt cog wasn't attached properly and worked it's way loose, eventually mangling itself and breaking through the cambelt cover. So the sensor wasn't sensing the rotation of the cambelt. It was a very bizarre occurence and the mechanic says he's never seen that in the 40 years he's worked with cars. It's all fixed today and drives fine.

Anyway my issue now is that there is oil in the water tank and milky residue under the oil cap which instantly sounds like a head gasket issue. However it has never over heated and there's no white/blue smoke so I just wanted to know if it actually is the head gasket or something else.
Is there a chance that it's linked with the cambelt issue?
I just want to be sure before replacing the head gasket as it's a costly job.