One time i had a horrible nose bleed and i almost passed out i got one every day for 4 days about twice a day and twice (not joking) it actually works put a tampon in your nose if u have a sister and leave it in the for like 5-10 minutes and it absorb the blood but blow your nose after just incase of a blood clot. But you should be fine.
Is it winter where you are and have you been spending a lot of time indoors? The humidity is very low and it could be drying out your mucus membrane. The blood is replenishing the moisture, temporarily. Try placing some vaseline in you nostrils after it stops.