yes...pms symptoms can be very similar to early pregnancy symptoms. Implantation can also happen around the same time you'd expect your period. Implantation bleeding is different from a normal period though. It's generally much lighter and spottier and doesn't last nearly as long as a period. If you have doubts as to if it's your period or implantation bleeding, you should take a test. Good luck..hope you get the answer you want.
Implantation bleeding usually occurs seven days after the last day of your last period. It can also range from 3 to ten days or no happen at all. Every woman is different. You can google it and get a ton of informative very helpful pages. I would suggest that is what you do. You will find definite answers that way.