Preschooler hands and lip swollen

Hey guys,

Last night my preschooler asked me to scratch her back as she does once in a while. After awhile the area looked like mosquito bites, we didn't think much and went to bed. Well this morning when we woke up her upper lip was bit puffy and her hands are seem to be swollen a little.

When she was an infant she had severe allergic reaction to something so we did allergy tests when she was 6 months and it was egg white and wheat. But since then it has gradually disappeared. So I have no idea what could've triggered these reactions. The things she ate that was not so normal for her were: strawberry imported from China, crackers. Any idea guys?

Please help..