Hi,
I've gone through your query and I understand quite well your concern.
Based on what you referred to me these symptoms after alcohol consuming, are related to gastro-esophageal reflux disease (GERD) 
chest pain.
GERD occurs when the lower esophageal sfincter opens spontaneously or doesn't close properly and stomach contains arise into esophageus which cause a kind of pressure under the 
sternum bones. These chest pains differ from those of 
heart disease related because this chest pain of GERD tend to get much better as you straighten your body to a sitting or standing position. Bending and lying down can make GERD symptoms much worse and what is important to know, they become worse particularly after eating!! (while heart disease related symptoms doesn't change neither with the change of position , nor to food intake)
Alcohool can irritate 
gastric mucosa.
So, in this case I suggest you to follow these steps:
1. Try OTC 
Zantac or 
Prilosec a few hours before you drink or before the symptoms begin.
2. Drink plenty of water because alcohol intake causes dehydration!!
3.Avoid spicy, junk, fried foods, coffee drinks or alcohol
4. Try to minimise stress because it worsen GERD symptoms.
5. Your doctor may prescribe you also 
proton pump inhibitiors (PPI) medications which reduces acid production in your stomach.
If your symptoms get worse, please consult to a gastroenterologist to make a further clinical evaluation.
Take care of yourself
Dr. Ermira BIU