Impossible to estimate from the information above. Higher chance than with a typical domestic vehicle. But if it didn't get too hot, for too long, you could be fine. It isn't that it warps the head with every overheat, it is just that when it does overheat and warp something, it is expensive.

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2007 X3 3.0si, 6 MT, Premium, White

Retired:
2008 535i, 6 MT, M Sport, Premium, Space Grey
2003 X5 3.0 Steptronic, Premium, Titanium Silver
2002 325xi 5 MT, Steel Grey
2004 Z4 3.0 Premium, Sport, SMG, Maldives Blue