First of all, the medications given by your Physician are correct...please continue them as advised.
The streak of blood along with mucous can be due to minor trauma to the respiratory tract
As the amount of blood is less, there is no need of concern.
It can be taken care of by managing the cough by intake of anti tussive & anti histamine
However, as the color of the mucus is yellow, bacterial infection can be suspected.
This needs to be managed with anti biotics, based on culture & sensitivity reports.
So, kindly visit your treating physician & discuss regarding this.
Investigations like complete blood count
, X ray
chest & bronchoscopy
will be helpful in ruling out any pathological cause for the symptoms.
Till then, maintain adequate hydration & nutrition status, take proper rest & avoid cold & other allergens.
There is no need to worry, you will be fine.
Wishing you a good health.