TTC for 5 mo. Took test 4 days before period and got a light but clearly visble BFP! Can this be correct?!?

My cycle isnt due till Friday but I am super impatient and took a test about an hour ago and its pos. The line is lighter than the other line but it is very visible. But I took a test last Thurs..BFN!! Again on Sunday..BFN! But for some reason I just felt like I should take my last one (i bought a 3 pk) and its a pos..Is this possible?? Specially since Im not due for my cycle yet?? I am SUPER excited and just need some advice. I am a proud mom of 5 kids and never tested early with them so I dont know if its correct or not. I have been having symptoms like fatigue and increased urination.