Hello from JustAnswer.
The immediate issue is the lower blood pressure
. This is considered a significant drop in blood pressure, but it is not bad if it is not associated with any symptoms.
The most common cause for this would be that you are low in fluids. Alcoholic beverages tend to be dehydrating. The alcohol can have a direct effect on blood pressure, but is usually not seen with only a few beers.
If you are not having any symptoms, it would be OK to drink a couple of liters of hydrating liquids, either fruit juices or sports drinks. Note that energy drinks tend to have a large amount of caffeine and should also be avoided. The sports drinks that are helpful are the ones intended for hydration, such as Gatorade or Powerade.
If the blood pressure drops below 90/60 or if it becomes associated with significant lightheadedness or a sensation that you are about to faint, then it would be more worrisome and it would be appropriate for you to be seen urgently.
However, this will usually improve with hydration.
For the long term, it is desirable to keep the blood pressure below 140/90, and sometimes your blood pressure is OK and other times it is not. The usual first step to get control of this pattern is lifestyle changes, including eating a healthy diet, avoid all salt that does not come naturally in the food, exercising regularly, achieving and/or maintaining ideal body weight, and stopping the use of tobacco and alcohol.
If I can provide any further information, please let me know.