I can get severe mood swings but never show them?

I get a bunch of mood swings. Sometimes I can be euphoric and then a few minutes later I can feel guilty about something that happened two years ago. This goes on constantly throughout the day. But the werid thing, is that I hardly ever show these mood swings. They are only in my head. They are so private, that I have been told I do not have a mood disorder. I appear to be very stable. I'm not saying I'm not stable, I'm actually doing very well. I can snap out of these mood swings quickly by using mindfulness and distractions, but they always come back. I can have mood swings several times an hour, but I hardly ever show any type of mood swings. I actually appear to be dull and affectionless. I usually just keep to myself and am quiet. Yet I am very competitive, slightly conceited, and often judgmental. I do have severe PMDD, and I am a completely different person in a bad way when I am PMSing. But In general, I seem emotionless. Does anyone know why I have so many mood swings but don't vocalize them? I've never heard of any other cases. Maybe I just have good control over them?

Do you see a doctor? Maybe one could give a more specific answer..
But yeah, I think some people are just good at hiding it. This doesn't change the fact that you're still hurting, though, and that's the important part.

Seeing a Therapist would probably be helpful in your trying to figure out what why and when these daily events happen.

Same here, I have not figure it out. Because when that happen, I would try my best to return back to current cativity and despise the thoughts. So far, it's not affecting my routine too much.

I'm not sure what your background is, or what you've looked into regarding mental health possibilities - but have you considered that it may be Rapid Cycling Bi-polar Disorder (ofcorse, always consult your doctor, I'm just offering a possibility).
This is a condition that affects a very small percentage of people who suffer from bipolar mood disorder.
It's characterized by extreme, quickly changing mood shifts (sometimes within minutes of each other).

I see both a psychiatrist and thearapist. My doctor says I am not bipolar because I do not have manic episodes. My therapists asks about my moods but I don't think she is concerned about them because I can hold down a job and am stable. I was originally diagnosed with bipolar but then that got taken off my charts because my mood swings stopped visibly happening. That was when I was a teenager anyways, and teenagers are moody in general. There was a brief time when a treatment place thought I had BPD, but after I got on seasonale birth control and only got my period 4 times a year, it was evident that
I had bad PMDD and not BPD. Currently, I'm diagnosed with PMDD, GAD, SAD and social anxiety disorder.

I have never heard of rapid cycling bipolar. It sounds interesting though.

I don't think anyone is looking into giving me any more diagnosis, since I am not having any problems.

I see my doctor in a couple of weeks, and I think I'll talk to him about this.
Thanks everyone.