please HELP!!!

Okay i am a first time mom and my daughter had to get her prevnar shot seperately because they didnt have the shipment in at the time of her 4 month visit. She has been coughing and conjested and throwing up mucus all this week since the shot and her front fontanelle looks a little raised and when i touch it it feels like a little pocket of fluid it doesnt ever go down and i dont know if its just the way  her head is expanding because shes getting bigger or if its really a problem that i should have her seen!