is it bad? does it spread?

It looks like bacterial leaf spot, most likely from a period of high humidity.  If humidity decreases it may stop spreading by itself but the worst of the leaves might as well be removed. 
 
If they're all like that then I'd just isolate the plant instead as they will produce a bit of energy for growing new leaves until they get bad enough to fall off on their own, but once you have new leaf growth you don't want that touching them, and you don't want to let the infected leaves get wet from rain or watering as that will spread it.
 
If the only ones infected are lower leaves then it may have splashed up from the soil.
 
To weird the humidity in my room hasn't been or 50% and a fan is blowing constant.  The plant has lots of new grow and I've been removing the affected leaves.  It's only my two Aji yellows that are showing signs of this. Hope it stops soon. Maybe that strian or pepper is more susceptible to it?
 
Are you getting the leaves wet when you water it?  Insects can also transfer bacteria, or it can be on seed then it multiplies in soil later.  No matter what type of pepper there has to be a method of infection.  None of them just randomly start rotting.
 
Nope not getting them wet. I think it came from the soil after transplant. Turning the plants upside down to get them out of the cup dirt got on the underneath of the leaves I believe it start there. But all in all its not spreading like crazy and humidity is low. I guess I'll just have to wait and see.
 
I had a similar thing a while ago. I kinda ignored mine for a while and it spread thru half my crop. To remedy the situation i removed the infected leaves bagged em and binned em. Wash you hands before touching the plants again after this. I then sprayed plants with liquid copper as per directions on bottle. Spray the stems as well. It knocked it on the head for me and I hope this helps you out.
 
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