<s>[INST] Hello! My 3 year old son went swimming to our gym pool with his dad, and after they were done, he started being very cold. After we got home we covered him with clohes and blanket. Maybe and hour after that he got fever. Gave him ibuprofen, fever went down, but it was back in few hours. My husband also said that my son may have swallowed some of the pool water. What can be the problem? Should I take him to the doctor in the morning? Thank you [/INST] Hi... Thank you for consulting in Chat Doctor. You did right in giving him Ibuprofen. Fever of few hours without any localizing signs could as well a viral illness. Usually rather than fever, what is more important is the activity of the child, in between 2 fever episodes on the same day. If the kid is active and playing around when there is no fever, it is probably viral illness and it doesn't require antibiotics at all. Once viral fever comes it will there for 4-7 days. So do not worry about duration if the kid is active. Hope my answer was helpful for you.  I am happy to help any time. Further clarifications and consultations on Chat Doctor are welcome. If you do not have any clarifications, you can close the discussion and rate the answer. Wish your kid good health. </s>