Re: AR ds just suddenly started screaming sore tummy
They could have done a dip test of urine at out of hours. If white cells/blood show up it's indicative of a potential infection and they would usually start antibiotics. A sample is then sent off which will confirm whether there is an infection and will also allow them to check whether the correct antibiotic has been prescribed. The lab results usually take 2 days. It is not ideal for a suspected uti to go untreated that is why they start AB's if they get stuff showing up in the dip test.
If you still suspect a uti in the morning I would ask the surgery to do a dip test on the sample before its sent to the lab.
If your little boy gets the rigors again with his fever nurofen has worked really quickly on M for reducing the fever quickly.