A log is the only way to tell whether it is doing anything for you.
Each day: date, whether you took it, energy (1 to 5), mood (1 to 5), sleep hours and quality (1 to 5), activity, and any note such as stomach upset or a stressful day. Use the same scale every day.
Average each week and compare with your baseline. Look for a trend over several weeks. Note other changes you made, since they muddy the result. Our earlier post on tracking how you feel covers the principle. Review at day 30 and day 50.