My bp is always on the lower side 80/54 avg..i take metoprolol 12.5 mg twice daily...is it concerning?

Somewhat: Your blood pressure may be too low for optimal health. As a general rule, maintaining a diastolic (bottom number) of at least 70 on average, if possible, is most likely to achieve a better outcome in the long run. This is especially true if you have seen a frequent tendency to feel light-headed after standing up. You may need an adjustment of one or more of your medicines. Talk to your prescriber.