After being bitten by a mosquito, your baby’s handback is swollen and red. How should you handle the situation?

My son is 5 months and 2 days old. He was bitten by mosquitoes three nights ago when he was sleeping, and initially, there were just two small red dots. No special treatment was given. Today, when he went to bed, I found that the dots not only hadn’t healed but had also formed blisters, which are mainly due to an allergic reaction.