1). It should. If the herx is not severe, you don't have to stop completely. Just drop the dosage down to where you're comfortable and after the herx ends, slowly increase doses.
2). See above.
3). Are you mixing it in water or juice? If not, mix it in about 8 oz of liquid and let it sit for 10-15 minutes before drinking. You could also eat something before you take it if it makes you feel queasy. If you still feel alcohol effects, then switch to capsule or powder form for as many of the herbs as you can.
Buhner doesn't make it easy for those who want to avoid alcohol, but it can be done. I'm still at tiny doses on most of my tinctures, but I can't imagine taking full doses of all my tinctures. I'd be falling down drunk. I took a large dose of one the other day - like half a teaspoon and the taste of alcohol was overwhelming. I'm not a drinker.
You didn't mention dosages. If you're herxing you need to decrease your doses. Buhner's starting doses are very high in my opinion. Some people are fine with it, but others can only tolerate a drop or two of some herbs.