Advice about temp with cough

My 7 year old son has severe asthma and takes seratide 50 as well as salbutamol. Over the past few days he's had a horrible cough and started with a temperature. Took him to see the GP who gave him steroids and antibiotics but told me to take him to a&e if he became floppy. Since coming home his temperature has spiked (39 degrees) and dropped (35 degrees) it's fluctuating between the 2 and doesn't seem to settle. The cough is there and wakes him every couple of hours. Should I seek further advice as I'm concerned its his asthma more than a cold. The past few mornings he woke up and seemed well but after school he's exhausted. He's only been properly diagnosed with asthma for the past 9 months. Any help would be greatly appreciated.

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I'd give your out of hours gp a call.

If you call your normal gp.surgery there will either be a message with the number to call or you will be transferred to them, depends on your surgerys telephone system.