Vitamin ampoule is hot... Do you have any home care tips from experts? (I can't give up whitening ㅠㅠ)

My face has been looking so dull lately, so I took the plunge and bought a highly concentrated vitamin C ampoule ;; but my face stings a bit as soon as I apply it. Is this just something that needs an adjustment period? ㅠㅠ

Does anyone know of any home care tips that won't sting even sensitive skin like mine? I heard that mixing it with a moisturizing cream helps. If you have any home care tips of your own, please share them with me!

And I put this in the refrigerator because it turned brown, but are there any special home care tips for storage?

I want to get synergy at home while receiving Maypure care... I desperately need some home care tips on how to use vitamin ampoules well.

I'd love to brighten up with some proper home care tips.. Just give me one home care tip you all know! ^^