Brown Spotting...

Is brown spotting 7 days before a missed period always considered IB (Implantation Bleeding)? Or could it be something else? I want to wait a couple of days to see if I get AF but I'm 2 days late already. Please someone help me. I need an answer. 
I had brown spotting (in my panties and on paper) not enough for a pad. It was just a couple of times. I didn't think anything of it until I googled it 4 days later and it said "Implantation Bleeding" now I'm scared I might be pregnant. Should I test today or wait a few more days..? 
Sincerely, The Very Scared Teenager 😵  
My cycles are very normal 28 days, 3-4 days of bleeding. 
Not on any BCP
Use condoms, me and my boyfriend sometimes use the pull-out method but he never ejaculates in me. 
I haven't ever had any spotting like this before. Ever. 
I haven't ever been late before either. 
2 days late as of today!