lack of period

[whatstheworstthatcanhappen1]

Sorry for tmi but need to give some background.
My period is normally regular and starts with slight spotting which is then heavy for next two days then another couple of light days.
Last sat i started spotting, on time so expected period to start on the sunday but it didn't.
Friday this week started spotting again so expected it to start but nothing again.
I am getting a bit if period pain but nothing much.
I am not on any contraception as my husband had the snip about 3 years ago. I am 29 if that makes any difference? Has anyone experienced anything similar?