Hi @NVLINH
Uploading a lot of photos is not an issue in itself. Uploading photos that are not helpful and violate the guidelines can get you suspended. Many other violations can also get us suspended. Congratulations on getting unsuspended. Not everyone are so lucky. I myself have also been suspended twice.
You may want to take a look at How to Get In and Out of Trouble: The Main post
Cheers
Morten