Dear Rach878,
The emergency is at the time of purging.
If you throw up blood again, please go to your nearest Urgent Care or ER.
When you tear your esophagus: superficial tears can be self-healing, yet still need to check the upper digestive system for bleeding. There are also tears between esophagus and stomach, a rupture of the esophagus (25% die), a rupture of the stomach. The latter two cause acute and abrupt pain necessitating a visit to ER.
Blood in your vomit is not a good sign.