Delayed Periods With Scanty Flow, Intermittent Spotting, Had Unprotected Sex In Earlier Cycle. What Does This Indicate?

I was supposed to get my period on the 11th this month, but instead the bleeding came the 17th( my periods are always on time every month) Well, the first day was normal bleeding, the second day it was very light, and then i started spotting/barely any bleeding, the third day i bled lightly again for a min or two, then it just stopped, now I have been have light brown spotting and scanty pink spotting, light bleeding on and off that lasts a few minutes or sometimes even les than a minutes then i start spotting again (it s been 5 days of this on and off bleeding, and spotting). What does this mean? Last month I got my period the 11th, and had unprotected sex the 25th.