Did Nexplanon Change?

I Had nexplanon from 2013-2016 April and it was wonderful. I had it replaced cause it was due to expire April of this year and it's been a nightmare ever since. I've never experienced side effects like this before. I had severe mood swings for the first two weeks just crying for no reason I was a mess. It passed. I put on weight quick and I exercise 3-5 times a week I've gained 40 lbs. I still try to exercise but the added weight makes it difficult. Also my periods are running amok. My last period lasted 12 days the bleeding stopped 2 days ago. Started again yesterday and stopped today. The cramps started again yesterday and I still have them today. I still have mood swings here and there too.  Like this is ridiculous. Does anybody know if Nexplanon changed? I may try to call Merck but I might not get an answer back.