Loss at 13 weeks.

So I have been having issues with bleeding for a week. First I'm told I had a hematoma of some sort when I went to the ER for heavy bleeding.  The baby was fine, strong heartbeat full of energy. Last night I went back to the ER for pains. Again baby was moving so much they had a hard time getting good ultrasound pics  strong heart beat. I was diagnosed with a UTI and was told the hematoma was no longer there. I get home and start experiencing excruciating pains. I was home alone and had to call 911 because I had a huge gush or blood followed by more pain. On my way to the hospital I passed my baby. I was 13w4d. How can my baby be full of life 1 hour and gone the next. I was able to meet my little baby. So tiny but precious. I'm heartbroken. Idk how to feel. This may have been my only chance at motherhood. I have PCOS and they told me this was my miracle baby.