Miscarry/chemical 5dpo? Possible?

Nicole

Hi, I been having mild back pain and frequent urination ever since ovulation. Today is my 5dpo, woke up with a really lower backache. Then, it was gone after an hr. When my hub was driving me just now, he made an emergency break which made me jump. Then I started experiencing menses like cramp and backache again. Is it possible that miscarried or chemical occurred so early????