Thank you for your enquiry.
A common cold is caused by a virus and the symptoms that you've just described, "sore throat, fever, cough, runny nose and muscle ache", are very suggestive of a cold. However, in the early stages, bacterial sinusitis can also present in a similar fashion. A bacterial sinus infection (sinusitis) requires treatment with oral antibiotics while a common cold usually resolves on its on with adequate rest and hydration.
As a guide, if your cold-like or flu-like symptoms are worsening after 5 days or last longer than 10 days, antibiotics will likely be prescribed. Sometimes, if there are other symptoms suggesting a complicated sinusitis e.g. associated neurological symptoms (e.g. headaches, giddiness etc) or eye symptoms (eye redness, swelling or visual deficits), antibiotics will likely be started earlier.
If in doubt, it is best to visit a General Practitioner or an ENT Specialist for an assessment.
Hope this helps and all the best!