Temperature in 4.5 month old

Torie • God is #1 in my life <3

My baby woke up this morning feeling very hot. Took her temp. under her armpit (not comfortable doing rectal) at 6:30 am and it is at 100.6... Ftm so not sure when I need to be concerned. She nursed from one side and is back sleeping again.

Update: She has vomited twice after nursing