To give the Merc. a fair shot, one dose may not be enough unless you've already improved. If not, three times a day for 3 days, stopping if you get worse, stopping if you improve, starting again if the improvement slows down, would be a fairer test of Mercury.

Do you have any concomitant symptoms; something that's happening along with the cold? For example, when Merc. is the remedy, there is often bad breath, drooling/excessive salivation; chills, sweating which doesn't alleviate the symptoms--any one or all of the above. If none of these apply, what sort of concomitant symptoms are you having, including mental symptoms as they depart from your usual state?

Another thing we can do is take the case of the cold before it was disrupted by the medicines--and possibly made worse by them. Can you describe the original cold? Which side the sore throat was on, what pain sensation you had, how it felt swallowing, did the pain extend to the ear, were there swollen glands, what color and consistency was the discharge, what may have caused this cold in terms of weather, emotions,
loss of sleep, and so on; was there a fever, sudden onset or slow; thirst or appetite affected,
chillier or warmer than usual, any modalities
(the things you find aggravating or soothing--could be a hot bath, company of friends, music,
warm rooms, blankets, cold compresses and so on)....I'll stop here as I've given you enough to think about.

Snoopy