Blood drawn 3 days ago. Bruise with dark purple line through it at draw site. Muscles hurt on that arm, especially upper arm. Should I worry?

No. It is probably a superficial inflammation of the vein and will go away in time. It might get had first .
Usually not. To draw blood out of the vein, the needle punctures it. Sometimes the hole does not seal off right away and blood leaks out under the skin causing a bruise. Sometimes instead of puncturing a vain, the needle accidentally punctures an artery and the bleeding can be more substantial, but even in that case the bleeding usually stops by itself. If the pain continues or is severe see a doctor.