Chills after taking antibiotics. It?

Hi I had cold, sore throat on Friday which was a kind of viral infection which spread from my husband. Since I already have sinusitis, there was strong facial pain and pressure in face and ears. I visited ENT and prescribed with Mega CV 625 (thrice daily for 1 week), Febrex plus and Voveran D. I started medicines on Friday night, while symptoms are better now, I got heavy chills and shivering yesterday night, today I feel a Guiddiness with nausea and pain on one side of face due to which I can't get up. Can I stop the medicines now, as I need to travel in flight on Tuesday which would be difficult with these side effects. Kindly suggest what can I do to overcome the situation? I am worried about heavy dosage (21 tablets) of antibiotics, as I just completed 4 in that. What will happen if I stop it? Thanks.