Nosebleed and now my chest hurts and i'm super dizzy.?

This morning I had a nose bleed that wouldn't stop so i grabbed some tissues and held it to my nose, and eventually fell asleep but then when I woke up my nose started bleeding again. It bled ALOT. But anyway I got in the shower and i started coughing really bad and blood came out, and i had the taste of blood in my mouth. Then i got really dizzy and i couldn't stand up so i got out and still, right now, i feel dizzy when i stand up and woozy nauseas. Also my chest hurts. I'm not sure if all that is related to my nose bleed but right after the nose bleed thing. What could this be? Is it serious? And what should i do?