should I be worried?

So I just found out I'm pregnant 2 days ago. I'm 12dpo. FRER second line got darker yesterday. Well I took a Clearblue Digital this morning (regular, not the weeks estimator) and it came back "Not Pregnant". In the same pee cup, I took another FRER and it came back the same faint line, no darker, exactly the same as yesterday's. Should I be worried?