Early in the treatment the instructions said "no alcohol". I quit. Over time I saw more things that said a drink or two was ok but I figured it was easier to abstain than to start and then stop before even getting a good buzz. Others may find staying in moderation to be less of an issue. Binge drinking, for certain, is out.

Even the most stable and long-term of Warfarin users get inexplicable spikes sometimes. Frequent testing can catch such spikes while they are down in the 3.x or 4.x range and still less dangerous, but cannot eliminate them. If it should come to pass that you become a long-term user then you may investigate low-cost home testing.
Going from 5.7 to 1.6 sounds normal after a 2-day skip, since Warfarin's half-life is about 36 hours subject to individual variation.

Have a drink or two, nothing crazy, but it'll be fine. I've learned over the years what my limit is with drinking in regards to warfarin. Really, you don't want to get impaired so that you risk falling, hurting yourself, while on warfarin. I've had absolutely no issues with alcohol and warfarin / INR.

INR fluctuations happen. A virus, OTC meds, eating differently, increased/decreased activity, etc can impact it. I'll be coasting along for months and months, and then something triggers a change. Who knows. I just kind of go with the flow, let them adjust the dosage and try not to over-think it or make myself nuts about it. I personally think having a home monitor is a nice convenience but not something you need to have to make this work. It doesn't change the fact that your INR will fluctuate. It just allows you to catch it sooner, but that would mean you'd have to be testing your INR all the time, which I think is kind of excessive and obsessive. I've tested since 2007 without a home monitor. It's doable and once we got to a good dosage for me (took about a year), rarely have I had to test more than once a month. But it's what you're comfortable with., what you're lifestyle allows, etc

As always, thanks for the imput! I guess I will just go with the flow that night. Typically, I have found that if I feel like having a beer or two, O'Douls does the job. But then again, at times, there is nothing quite like the real thing. As you both said though, I think the key is knowing the limit and being able to stop at that.
I was also completely wrong on thinking my INR had gone up too high again. It was 1.92. So looks like I am heading back into range. This is all pretty new to me so while I feel I have a pretty good grasp on things, I still question a lot. I would so much rather hear from other people who live it then just rely on doctors alone. Makes for a nice balance I think!
Thanks again.

@jean - how quickly your INR drops may be related to how high of a dose of warfarin you require on a regular basis. my INR dropped from about 2.5 to 1.3 in 3 days off of warfarin to prep for a surgery. my coumadin clinic told me that's probably because i take 10 mgs daily. they said that the higher the dose, the more quickly a user's INR drops when they stop taking the med.