Kid puked when just had flu 2 weeks ago

My son is 15 months. 2 weeks ago he woke up in the middle of the night and threw up only once. I thought he just ate too much or something. Was acting completely fine and was fine the next day. But then a couple days later my 4 year old was up half the night puking.

Well it feels like we just got over that and they now caught a cold. Bad runny noses and coughs which they currently have. Low grade fevers.

My son ate dinner fine and we ran to the store to get diapers and he was acting funny but I thought maybe he was just tired. He was leaning his head back on the cart and being very quiet. Well when we got to the car he projectile puked all over himself and car seat.

I checked his temp as soon as we got home and it was 101. He was whiny but went right to sleep and he’s been sleeping since about 20 mins.

Is it normal to get a stomach bug back to back like this? Has that happened to anyone else? And also he currently has a cold. Can you have a cold and stomachs bug at the same time?

I feel so bad they just got over being sick. But he did eat A LOT at dinner tonight. I’m trying to convince myself he just ate too much for my anxiety 😅