If my dentist accidentally injected the lidocaine into a blood vessel, 37mg of lidocaine, would i die? i know about aspiration but can still happen accidentally?

Not from this: Whatever ill-effect you were going to have from this mishap, it is over. You are not going to die from this. Have a healthy diet, exercise 30 minutes/day, drink plenty of water daily so your urine is mostly colorless, have safe sex, no tobacco alcohol weed or street drugs. For nutrition: http://www.choosemyplate.gov/.

Irrational Fear: This question has been answered in another post. Each carpule contains 1.7ml of anesthetic, 34mg lidocaine @ 2%. Where does 37mg fit into this equation? I would speculate that anything is possible, but also highly unlikely in your scenario.

No: First, your math is fuzzy. Second, if this was possible you would be dead already. Third, your body metabolizes lidocaine rapidly, especially nit widely distributed by the circulatory system. Fourth, how often have you heard of this happening on the nightly news or read about it on social media, like never.