Could Light Periods Along With Bloating And Nausea Indicate Implantation Bleeding?

My name is Melissa I am 20 years old. I became sexually active at the age of 18. I have never had any kind of pregnancy scares before. I recently had what I can only think of as implatation bleeding. It was very light spotting (did not need a tampon) for the 3 to 4 days it lasted. The spotting started around the same time that my period must have began. What are the chances that it was in fact implatation bleeding and not just a light period ( my periods usually last the full 7 days). I have been noticing that i have been very bloated and have been dealing with slight nausea.
Please let me know what you think and where i should go from here... i dont have any health insurance