I agree it's a growth spurt around this time.
But if he gets a temp, is really hard to settle and screams non stop do take him to the doc's or ring health line 0800 611 116 for advice or plunket line 0800933 922. They are both great services.Not to scare you but babies go down hill really fast.
He could just be over tired.
Try a deep warm bath to relax him.
Put him in the pram amd wheel him up and down hall way or around lounge or over join in carpet.
Do you have a sling or moby wrap?
If not use a strong sheet and make a sling wear him close so he can smell you and hear your heart beat.
cuddle him to sleep, leave a piece of your clothing in his cot so he can smell your scent.
I used to tuck a top at the end of the cot so it was away from his face e.t.c but my smell was around him.
do you have a swing or bouncer? put him in that and rock him.
Or put him in his car seat/capsule and put a mussie or light cloth over it and rock him to sleep.
A plunket nurse told me about this it worked a treat with DS1 who would scream all the time!
Once he's asleep in the capsule transfer him to the cot.
good luck

hope the tips help!