Last night i had a nightmare, i'd like to know what it means?

this is the second night in a row that i've had a nightmare, and i rarely dream. they aren't the same dream both nights. the first night i was walking home from my new job and a little boy on a bike was following me until i made a turn and there was a chinese man that chased me up a flight of stairs. when i got to the top, i found something to kill him with but woke up before he got to me. the second dream was of me and my ex (that i just started talking to after 3 years with no communication) were in my house and a biker with long hair and his girlfriend were trying to break in, but they kept looking into my window. when they realized that i was home the guy kept walking around to different windows and making eye contact with me, he was really intimidating. i kept myself between him and my ex at all times. when waking up from both dreams, i was out of breath and my heart was pounding hard and fast, and i couldn't go back to sleep if i tried.