Implantation Bleeding?

Okay so on my last period I only bled for two days and it wasn't really heavy it barely showed on the tip of my tampon and the rest of the three days there was only brown blood and it wasn't heavy it just showed on my toilet paper whenever I wiped and today I was in line at the store and just had this awful nausea come up I gagged and knew if I opened my mouth I would puke right there and then. Thankfully I managed to get out before I blew chunks everywhere. I'm just wondering could my last period have been implantation bleeding? Thank you for reading this and I'm sorry it's so long!