Miscarriage without knowing ?

Is it POSSIBLE ? July 17th , my son's birthday , me and my SO had sex . On the 22nd was my ovulation day, the next day I felt all nauseous out of nowhere, day after the that I been very light headed / dizzy . August 1-3 I bled and the next 2 days I spotted which isn't normal because my cycle last 5 days . So on the 7th I discovered a pink spot .. Later that month , 27th-29th I bled again but the 30th-31st I spotted ..

Ugh , then September 8, I had a blood pregnancy test done but the results was negative & my period went back to normal =/

Could I have had a miscarriage without knowing ? Or you think it was something else ...