21 y/o active female. resting hr around 100bpm. resting bp averages 105/68. history of heart disease in my immediate family. average weight, occasional fainting spells. should i get checked?

YesPrimarilyDrivers: I have answered similar questions many time on healthtap. While atherosclerosis typically begins later childhood, your stated age, sex, low normal BP & no smoking are best odds of not yet having advanced disease. Yet best check & optimize lipoproteins(nmr particle test), LDL (≤700 umol/l), large HDL (≥9 umol/l), hba1c ≤5.0%, hflc, consider event monitor for potential arrhythmia basis for fainting.

Fainting : Probably ok but fainting of concern, certainly wouldn't hurt to get checked out.

Yes: Because of the occasional fainting spells. It sounds like postural hypotension that might be associated with hypoglycemia.