Reputation not appearing on username flyout
I have gained reputation through last week on SO, but they don't appear on my profile menu. Is this a bug? (the reputation of week is zero)
month cumulative totals shown in that overview are not referring to the last 7 or 30 days, but to the calendar week and month. Stack Exchange weeks start on Sunday, and the month on the first day of the calendar month.
Since you have yet to gain reputation today your total for this week is still 0.