How does this happen!?!? 😢

Woke up I'm officially 3 days late. I took a test this morning, and I had a faint positive! I've never been so excited in my whole life!! We have been trying for about 6 months now so this is great! And it being Fathers Day, I couldn't wait to tell him! We were both so excited!! ..... THEN something horrible happened, I started my period tonight!! How does that even happen! I was so upset, angry, and embarrassed that I shared this news only to disappoint him and myself. Ugh! Has this happened to anyone?