Is it normal to have a little rectal bleeding after using a dildo? It's frightening to me and i don't know what to do. Help! ?

No. You are not supposed to be bleeding. You tore something. Put some polysporin up there and let it heal.

Define "a little".

It's not ideal but also not all that unusual to have enough to mark the toilet paper or even tint the water in the toilet. Next time be more gentle.

likely a hemmeroid

That's not a bug, it's a feature

It's normal to some degree although excessive amounts of blood can cause a problem. I would suggest that you stop using it back there and use it as was intended. It's much more pleasurable in front. If you insist on anal, let it heal well first, and then be certain you use a sufficient amount of Ky jelly as a lubricant.

Why the heck are you using this at the rectal area???  It is NOT meant to be used there.

If are bleeding after vaginal insertion you need to see a gynecologist.  Rectal bleeding is not normal from vaginal penetration...ever.  You may have torn something or other things are going on (like PCOS or endometriosis) that you aren't yet aware of.  It needs to be checked out.