Nose bleed due to blood clots?

Earlier I had a nose bleed for like 30 minutes just gushing blood like crazy and I decided to plug one nose and blow air outta the nostril that was bleeding and 2 huge blood clots came out Fairly big but through the whole nose bleed maybe 2-4 clots came out. Should I be concerned in any way I have allergies my parents seem to think its because I sleep with my dog I think its my outdoor allergies to trees and grad and pollen but please help someone