mildew above window worried about black toxic mould

[Nighttime pacer]

Hi all
I've got a new worry. Black toxic mould.
I've noticed that in my bedroom I have a square bay and in the top corners of it there is a small amount of black mould. Just some spots like mildew. I got a cloth and wiped it and some came off. I'm now panicking that it's toxic black mould and I've put myself at danger. I'm guessing that a tiny amount of mildew or black mould can't be that bad. It's only a couple of strips about 8cm by a cm. I'm going to get a mask and some spray and tackle it all tomorrow. I've got some tea tree oil I can mix with water and spray on it tonight.
I assume that toxic black mould is only a problem if there's a lot of it.
A lot of what I read online seems to be from companies wanting to do the work.
I wish I didn't automatically panic.
Thanks for reading this as always.
Nighttime Pacer

[Captain irrational]

Honestly the "dangers" of mould are ridiculously overstated. Every house will have a bit of mould somewhere, especially in the Winter months when people aren't opening their windows as much.

A mask is totally uneccessary, just clean it off with a bit of disinfectant and you'll be fine.

[Annaboodle]

Every flat or house I've lived in with old windows that really could do with replacing has this. I just wipe it off with some white wine vinegar or similar. You can get black mould remover. The poster above is right about the dangers being overstated. A little bit of mould around your windows will not hurt you. My sister lived in a place once where it really was a problem - by which I mean most of the ceiling and part of the wall was covered (landlord from hell).

[Magic]

We live in a very old house. We had coal fires then and wooden windows. We had no mould or mildew. With central heating and double glazing we have the mildew/mould which is a pest. I just keep wipe it off. Has not harmed us.
Since we had the humidifier it has helped a lot.

[Nighttime pacer]

Thanks everyone for your comments.
I've cleaned it with mold remover.
I open the windows every day to air the room but maybe it was caused by sleeping with the windows shut. In future even if it's cold I'll open the end windows near the corners just a crack so there's some airflow through the night.
The other rooms where no-one sleeps are fine.
I've relaxed about it now as I realise how common a bit of mold is, we do live in Britain and it's wet and cold.
Today I started reading a new book which was recommended by anxiety uk which is called "overcoming worry" it so far seems great.
I must try not to be so disappointed if I worry about as I realise that doesn't help anything.
Good luck everyone.
Nighttime pacer