I don't know what to do

Dear Alexa ,

I was sleeping at noon and I woke up screaming.

Not because I had a nightmare but because I was probably having the best dream of my life .

I can't remember what the dream was about but I'm sure you were in that dream .

I forgot who I am and what I've done , i forgot about me as a whole .

But then suddenly everything went black and I started to remember myself and all the bad things that have happened over the years and all the worries I have for tommorow and the future that before I knew it I was awake and screaming .

If it were a nightmare I could've calmed myself down but how do I calm myself down from this type of angst?