Cryptic pregnancy or false positive?

Don’t even know where to start, haven’t had a period since the start of February we were trying to conceive so gutted when it arrived (late) but anyway continued ttc my next period didn’t arrive but I can be irregular so again waited bit longer I just assumed it was stress delaying it as it was really stressful time in my life second period doesn’t arrive so I tested and it was negative! 3 missed periods I got a doctors appointment had some tests done all came back normal I’m thinking possible PCOs at this time I had lots of hormonal related symptoms and some pregnancy symptoms but again just assumed it’s a severe hormonal imbalance I am currently awaiting doctors appointment for this week. Last few days I have felt movement really low down in my pelvis like flutters I just assumed gas, well today i randomly took a pregnancy test just to rule it out that I wasn’t crazy it came positive instantly and the lines dark, I’m now thinking am I crazy cause I can’t possibly be? How could I miss it could it be false? Will test again in the morning. Has anyone ever experienced this? X