I honestly do not know what this smell maybe. If you feel it maybe due to some kind spirit or being you could try to look it up online and find out that way. In the meantime, do a cleanse and purification of your new home and yourself since it seems to be linked to you. Also, look into if there have been problems with the sewege system in your town it could be that kind of issue. Either way, hopefully nsomeone may have an idea what you are attracting but definitely look into different reasons for it to find the best solution as you cleanse and purify.
A rotten smell can indicate a demonic being, especially if you smell it throughout your house as if it moves. Granted, the smell could be the result of many logical things, like a sewage leak, but an animal like a rodent could of gotten between the walls and died, or you dropped some food a while ago. Could also be mold if you threw a wet towel in your closet and forgot about it, or mildew especially if you just moved something out of storage in the basement. I would clean your room or perhaps house [if its in multiple areas] thoroughly. If you live in an apartment or a suburban area ask your neighbours about any smells or septic issues.
If it is a demon, there would be many more signs like sounds, the feeling of being watched, injuries, and/or objects being broken or go missing.