My 3 year old daughter spiked a random temp of 38.5 she was given paracetamol with no effect. but 2 hours after it went and she was fine. any ideas?

Fever spike: The slight rise in temp can be caused by a variety of reasons.Such as increased activity, food or being overdressed to name a few.

Not unusual : For children to spike a fever and resolved on its own with or without antipyretics within a few hours. At times, that is the only pre-warning sign preceding a viral or bacterial illness days later. At times none at all . Just observe for now. If recurrent fever with more signs and symptoms, check back or consult with your pediatrician.