Spotting question

Hi ladies! So I'm pretty new to sex.. Just had it for the first time around thanksgiving. I'm 19 and on the Skyla IUD for birth control, which I've been on since July. It's made my period go away (which is normal for Skyla) but today I've gotten some spotting. I know spotting can be pretty normal for a good 6+ months on Skyla, but this is the first time it's happened in a while. I had sex 2 days ago, with a condom, and now it's spotting, but it hasn't after sex before. Being paranoid I google it and websites said it could be caused from implantation. I'm gonna get plan B just in case as a precaution, but should I be worried or does this sound kinda normal?