Difficult_Waltz_3614's journey

I had my third round interview for a position last Friday, and it's now been almost two weeks without any updates. The hiring manager mentioned I would hear back by the end of last week, but it's already Tuesday and I'm still waiting. I sent a thank you note right after the interview, and I felt it went really well. I'm wondering if I should follow up again. Should I wait until this Friday or the following Monday to reach out, or should I just hold off? Any advice would be appreciated.