Hello~I would certainly go to the ER and let them know what happened, it was a small amount, it is probably nothing to worry about, but it is always a good idea to have issues like this checked.
If you work in a hospital, lab, or clinic, you should contact human resources or infection control ASAP. However, it does not sound like a very small amount of mercury is likely to do permanent harm. Here's a case report, for reference: https://www.ncbi.nlm.nih.gov/pubmed/11033922
You should definitely see a doctor to make sure you don't end up with mercury poisoning.