Followed back his ex on insta

So he followed his ex back on insta
I created a huge scene (I’m a dramatic person overall in life)
He unfollowed her and now he’s telling me I did not cheat I just followed her back (that is kinda true)
(Same girl he cheated me on with like in 2014 )
(*** after that I’ve done my share of shitty things to him too when we were back )
He has been really patient with me all along
I’m the girl who’s been around since I was 16 and he was 18 .
We were planning to get married since a few months now
He has not cheated on me in this situation but this thing is not sitting well with me and we are not talking since 2 days … I called him multiple times ,no answer…
What should I do ?