I know exactly what you mean. Some months ago I was only able to feel anger, frustration, stress, anxiety sometimes, happiness when I achieved something really good for me, boredom and not much more. These emotions I felt weren't much intense, they were pretty empty and I wasn't much able to express them - I couldn't and I didn't know how to do so.

Now I can't barely feel anything, just boredom, frustration, anger, maybe happiness, but I'm usually numb and laid-back, as if I didn't have any emotion left. There may be many reasons why this happens to you.

In my case, I don't know why, but I must say that I never enjoyed feeling emotions, including positive ones and these emotions harmed me a lot: love, anger, sadness... I just kept some of these emotions because it made me stronger. I enjoy some emotions, though, like happiness, but it's not very intense and it's just temporal, it only lasts some minutes. My top philosophical question is, "are emotions real?" just because of this.

Even though I'm not able to feel intensely emotions, I would like to feel more than just boredom and frustration. If something bad happened to me right now, I would be calmed and I would automatically think, "anything that happens now won't matter tomorrow". I wouldn't feel anxiety or fear.