well the spell will not work obviously.
if you made a love jar for a specific person then it'll probably mean they won't like you no matter how many spells you do. if it was just to attract more love, you might have a small period of people being mean to you. otherwise, you're not cursed for life or anything. try cleansing the area, and don't let any negativity bother you [otherwise you might go into a negativity spiral and make things worse than they should be]
personally i would work on that temper. spells/deities/the universe has a way of teaching you lessons the hard way. this might be an isolated incident, but if you don't complete spells, or let your emotions rule you, you may find yourself in hot water later down the road.