HELP! Could his Amber Teething Necklace be causing this??

[Calluna]

Ss-storm it was almost 48hours. That's why I thought maybe it was cause of the necklace. I put it on him Monday morning at about 10 and he started at about 8am on Wednesday. Nothing else has changed, the only other thing I can think of is that maybe his neck is sore? He slept with his head on my arm last night, it still doesn't explain Wednesday though....
We're out for a drive atm to get him to sleep, and it's working, just have to drive around for a while and use up fuel we don't really have . At least he's asleep though.
Goodness I hope it's not a phase.

Thanks Cherished1, I was thinking I should give it another go when he's back to normal, at least then I'll know if it's causing the trouble.