Three weeks can feel like a very long time. You may like to ask your therapist for alternate options next time they are away.
Dsythymia doesn't have to be for life. Just the diagnosis comes from it being chronic. That doesn't mean that without adequate treatment it can't be resolved.
This doesn't sound like straight dysthymia to me. I suppose you can get ups and downs but it just doesn't seem right to me. Just a feeling.
I get that noise thing too when stressed and anxious. I have often gone around the house wearing earmuffs because everything was just way to loud.
Good luck for coping with the next three weeks.
michelle here thanks for that yeah ive got a phycotherapist which i will be going to see in 3 weeks i have had a really rough time which i have lost it a few times which i mean really lost it on people . my therapist is on holiday at moment so i am just hanging in there
I would make sure you have psychotherapy too as that can help address the underlying issues and help resolve the mood issues.
If you feel up sometimes and it's not part of a normal mood I would look at the possibility of bipolar or maybe even bpd. I think that you sound more anxious than depressed.