I can relate to this, as the result of my intensive meditation practice was that I wouldn’t experience emotions the usual way anymore, rather I experienced it all as ‘physical tension in my head’.
What I came to recognize is that when I felt physical tension in my head, I was actually experiencing an emotion, but repressing it. So that became my trigger to become aware that I was feeling something. It sounds like for you you can pick up on other physical symptoms - tightness in the chest or increased heart-rate.
What I found effective as a next step was to ask myself, “Ok, let’s say I am experiencing a negative emotion… what is it about? What is bothering me?” The really funny thing is that the next immediate thoughts would be “Well it can’t be A, that doesn’t really bother me, and it’s not B or C either, because I don’t really care about those, and it isn’t D…” Whereas A, B, C, and D were precisely, exactly what was bothering me!
So I came to see that whatever thoughts naturally arose/came up when I asked myself what’s wrong, the content of the thoughts (i.e. what they were about) was precisely what was bothering me, whether I was denying it or not.
Once I started to became comfortable with and able to admit to myself that things do bother me, that really made things a lot easier. And I’ve still had this even relatively recently, being ok with admitting something is bothering me - so it wasn’t an all-or-nothing flip of a switch.
The key seems to be being ok with experiencing negative feelings… once you become ok with this and you see that it’s not the end of the world, it doesn’t mean you are a ‘bad’ person (besides which it’s silly to categorize people as ‘good’ and ‘bad’ anyway), then that really takes the edge off the emotion. And then you can start finding it funny instead 
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