Hello, I'm new to this forum and i need help please

.I have a little tabby cat that is 2yrs old and a 3yr old hymalian or however that is spelled and i gave them both the feline focus 3 drops you put one drop in the corner of each eye and the remainder in each nostril equally as they inhale,anyways both my babys are so sick now they keep sneezing and coughing and are very congested their noses are also very red and extremely raw and my tabby cats breathe almost smells rotten

with that said they are still eating food and drinking normally.Is this a normal reaction or should i take them to the vet.