Late period question!

I recently switched period tracking apps and it says my period is now 12 days late but I don't think it's that many, I think I'm only 4 or so days late. I have a boyfriend of 4 years and we have had sex but it's all completely protected and I'm very careful about things. I have a clear discharge occurring. Should I take a test just to be sure? I have had things like this happen before. I have started working out a lot more and I am I freshman in college as a science major so I'm very stressed a lot. But I don't know what to think. Advice please?