First time in Thailand and unfamiliar, thus the question.

I am looking at booking a Thai VietJet flight arriving from CNX at 09.10 (VZ101) and then self-connect to the KL flight to AMS leaving at 12.15. I have my backpack (6-7kg) and one carry-on (12kg) and given the strict limits of one hand-luggage i am thinking of checking it in for the VietJet flight but no need to check-in for KL (take it with me). Is this enough time to do this self-transit? VZ101 is consistently on-time since May (landing well before 9am).