I believe your sig of the little girl only wearing a tshirt to be child porn, you have been reported to the tipline.

But, tiplines are nor operated by law enforcement in the UK and most other countries, an independent group (Internet Watch Foundation) reviews tips and based on the guidelines they have decide if they should forward it to the police or not.

They will need to fill in a report, somebody will spend not less than ten minutes of their time analysing your signature, hopefully agreeing with me that it is child porn, and filling in a report explaining if they take forward it to law enforcement and if they don't, why not. They might have a quick checkbox for the report.

If someone else reports you again it will be easier to troubleshoot because they will see on the logs that nothing was done last week. Or that it was already forwarded to law enforcement and there is no need to do it again.