Scared! Doc making me to do 5 week scan due to spotting and cramping

Amy
I mc last year when I was 8 weeks but didn't find it til my 12 week scan. Had no cramps or blood. Was a complete shock. 
Now I am 5 weeks pregnant and extremely happy. I had light spotting half way threw week 3 only when I wiped which I thought was implantation bleeding. And got a few strange cramps in my stomach only for a few days. Felt like my stomach was stretching. Had my first appt today with doc and he wudnt give me a blood test. Said I needed ultrasound asap. I'm booked tomorrow. I am so scared. Has anything like this happened to anyone else?