Hey Mike,
I'm pretty new here. Been dealing with my own version of cluster headaches for about 6 years now but just figured out what they were about a week ago. My primary doctor agreed that they are cluster headaches but I am following up with a Neuro soon for a more official diagnosis. In the meantime I have spent pretty much every spare moment I have reading up on cluster headaches, and here's what I know....
1. Go to a doctor. ASAP. What you have may or may not be clusters, and as far as I know we don't have a neurologist here that can diagnose you over the internet unfortunately. Anytime you are experiencing an abnormally severe headache it is a good idea to get checked out. You can't self diagnose, especially when some of the hallmark signs are missing (regularity of attacks is pretty much in the name.)
2. In answer to you first question...it's complicated. Cluster headaches are not necessarily a "progressive" disease but they seem similar to some other diseases like lupus or fibro that have flare ups and can get worse for a period of time for some people. Some people start episodic and then become chronic and then later go back to being episodic. So do they get worse? Maybe. Maybe not. The good news is there are new treatments being worked on and research being done (though definitely not as much as there should be.)
3. For the 2nd question: Don't do it! I can't speak for anyone else here, but every article I read lists alcohol as the primary trigger, most include nitroglycerin as well and mention not taking daytime naps as sleep seems to bring on cluster headaches. For me, if I am in a cluster period, a single alcoholic drink will guarantee me a few hours of the worst pain you can imagine coming within the hour. During my latest episode before learning what it was I decided to go to Applebees and have some long islands with friends. I barely made it home (not because I was intoxicated, but because the cluster was coming on hard by the time I left.) I tried a rum and coke at home the next night same thing. This is the only time I have had attacks outside of my usual 11pm-1am range.
Let me clarify here the following is my personal opinion and experience: The pain of clusters is this bad, I have drank alcohol every day for the last 5 years pretty much. Not binge drinking. Just one or two drinks maybe a few more for a special occasion occasionally, just something to help me sleep. It was my means of self medicating for anxiety and helped me sleep. During the last 5 years I have never gone more than 2 days without those drinks. Once I found out that alcohol was the trigger I quickly became cured of the desire to drink. I have been sober for almost a week now, and have had zero desire or temptation to have another. Haven't had an attack since either. Convenient timing probably as I was nearing the end of how long my typical episodes last anyway. Still, even though I'm pretty sure my episode is over, you couldn't pay me enough to have a drink right now. If you have cluster headaches alcohol is not worth it.
To simplify, if you have episodic cluster headaches and are in an active cycle:
Alcohol = Cluster Headache
Cluster Headache = Pain that defies imagination/description.
Therefore Alcohol = Pain that defies imagination/description.
4. 3rd question, as far as I know there is no way to know when you have exited an episode for sure other than going a week or so without headaches or maybe trying to drink and waiting to see what happens but like I said above, that's probably not the way to go. I'm still highly aware of every millimeter of that nerve on the left side of the face. It doesn't hurt, but it's like I can feel it. Like that feeling in your hands when you've been using the lawn mower and it's just a slight tingle to remind you of the vibration for a while after. I'm not sure if this is typical after a cycle or not. I don't remember. Probably was too preoccupied with worrying whether another was coming and I didn't think to write it down last time. Start keeping a headache journal and write these things down.
Hopefully you get to a neuro ASAP and hopefully they find a secondary cause of your headaches and it cures you. Hopefully you never had and never will have to experience a cluster. But if you did, this is one of the places to be. I've also found twitter to be surprisingly useful for finding information. There are a few clusterheads that post useful links pretty often. There are also some support groups on facebook that seem mildly useful, but harder to search and index imo.
Good Luck
BarcodeJ