Hi,
Spotting associated with a 5 week pregnancy is a cause of concern. You need to take adequate rest and avoid sex till the ultrasound scan is done. If the pregnancy is viable then progesterone support can be given and a miscarriage can be prevented.
There can be many causes for a miscarriage like hormonal imbalance, maternal medical conditions, abnormalities in the foetus etc. Consult your Doctor. Hope this helps.
The answer is based on information provided. Exact advice is not possible without a proper examination and investigations. You are requested to consult your Doctor. Take care and keep us posted.
I'm having a scan on Wednesday morning they have taken my bloods so hopefully that will show if anything is wrong. I'm really worried now :-/ :-(