Should I negotiate my job offer?

I just received a job offer that matches the upper end of the salary range I initially provided during the interview. However, after gaining a better understanding of the job’s responsibilities, I realize that I may have undervalued myself by approximately 10%. Unfortunately, I can’t compare this figure to a salary range since one wasn’t listed in the job posting. What do you think—should I negotiate? If you believe it’s worthwhile, how should I initiate that conversation or follow up with an email?