My son just had his 16 week jabs three days ago. He's always a bit unsettled after them but he seems worse this time. We just got over a big sleep regression and it seems to be returning after a week of good sleep. Has this happened to anyone else? He's crying for an 1.5 hours before bedtime and waking in pain in the night (arching back). Just wondering if this is common? Also he had a small fever for 24+ hours and have been giving calpol as needed