Does Serotonin level matter?

I recently had blood work done. I am meant to see my doctor on Wednesday to go over the results, but I received them early. I got them today in the mail. Everything on my blood work was perfect except for my serotonin level. My level is a 17. It says it's supposed to range from 50-100. So, should I be worried about my level being this low? I'm not sure what serotonin even is or what it does.