advice please!

So my prescription changed, and I asked my doctor if it was okay and safe to start the new pack as scheduled, she said yes. I was taking each pill correctly, then I took the last one of the second row late. Took it as soon as I could, rest of the week was on time then again, second to last pill I took it late. 
I read us on my prescription, Larin 1.5/30, and each article said I should be fine. My boyfriend and I had sex the day before my period, no protecting and used the pull out method. I know not the smartest idea because this has left me very on edge. I got my period on time. BUT a day after my period as over I had a little spotting, ever since then I thought it could be implantation bleeding. It was just that one time I spotted and it never happened again. 
I think I should take pregnancy test, but I really need advice on what you guys think, please