Rash and shortness of breath once I've drank alcohol

I'm a 34 year old male, fit and healthy normally only drink at the weekends, but the last 2 weekends once I've had a drink I've got a rash on my face, neck and shoulders, become hot and got short of breath, this last for about 30 minutes and takes about 30 minutes after that to get back to normal. I've not started drinking anymore or less than normal and haven't drank anything different than normal, could someone suggest what's wrong?