Why do my neck muscles feel sore after i've had one or two beers to drink? this is something i've experienced only after drinking.

Not common: Some people are more likely genetically to generate toxic compounds in their blood after drinking alcohol because of metabolic variants. Another possibility is that you experienced trauma sometime in the past and the alcohol use triggers you not feeling safe and hence the neck muscles contract and hurt. In Chinese medicine it might be explained by liver yang energy rising. I can only surmise