dark vein/colouration line has appeared.

I have read that it is important to look at color of hands, as its an indication of current health.
I have been reading lots this past week and using my own hands to try and learn from.
I noticed my hands are red and white blotches all week. Then today I have a noticed a change. They are still red with white blotches but also on both hands in the same place a thin dark vein running up from wrists & venus mount along my (weak) life line and then up across and through my head line and then branches/forks off to Saturn and Apollo fingers.

On both hands where the vein cuts across the head line it is showing up quite dark for a few mm. The rest of the vein pattern I have described is not hugely obvious , but the darker patch where it cross over the head line is. It is showing on both palmsand in the same place.

Does it mean anything or have I just had one 2 many coffees today?