Is 100/58 normal for a 22 year old female

That is low normal. From what I googled. I am not a healthcare professional. It is in the range that you might need to see a doctor.

If you are a 22 year old female who is physically active and in good shape, that's really not too bad. Are you athletic at all? Athletic people tend to run lower blood pressures.

As long as you aren't having symptoms, this might be normal for you.

Mine is close to that, maybe 105/65, and I'm 22 a few times over. The docs think I have great blood pressure, and can't believe it is still so low. Count your blessings and eat right.