If you are smoking it would indicate that your 151-to-Coke ratio is a little too high. Try adding a little more Coke until the smoke stops but not enough to take you below simmer.

As to your head hurting tomarrow, weeeell, first thing is I don't think there IS any marrow in your head.

Regardless, possible causes include:

1) You fell over. Possibly more than once.
2) Your 151-to-Coke ratio was still off - remember, practice makes perfect.
3) Your last cherry went into your drink and you chugged the cherry juice from it's jar: DO NOT chug cherry juice, it should be sipped slowly and delicately (just like, well, consider where the name came from) until just before the last drop which is the time to chug.
4) Then there's the lemon factor to consider: DID the juice run down your leg?
5) Stop hitting yourself in the head with the empty rum bottle. Yeah, you shoulda planned ahead so you wouldn't run out but relax, refills are just a store trip away!

Hope this helps. Keep up the good work and bottoms up! :)

Cola should be floated in a very thin layer over the top of the 151, protecting you from combustion. To drink the 151 you must practice breaking the surface tension just where you sip the cool refreshing beverage. Properly sipped the highly flamable 151 will never feel the cruel and oxidizing air. Should you have trouble keeping a good seal over the 151 use a straw.

Otherwise it's left hand Cigarette... Right hand drink and never the two shall meet....