Scabby lump on end of tail

I noticed this morning that Takara has got a scabby lump on the end of her tail that has been bleeding. I tried to push the hairs on the end of the tail away but all I can see is a big red mess

It's not bothering her in general, and she doesn't mind me touching her tail but when I try to touch the area that's hurt she tries to lick it, she's not snapping at me though so it can't hurt that much.

Lately she's been chasing her tail a lot and trying to chew it, she doesn't normally do it so do you think it's just that she's bitten it and could this just be because she's in season or is there perhaps an underlying problem? She's having a bath today and her next flea treatment which is due today but I just wondered if you think I ought to be concerned?

She hasn't got fleas, at least not to any degree because she had them as a pup (caught them at training) and you could see them all over her, I have looked and can't see any but she's also been scratching behind her ear a lot and as a result that's a big scabby mess aswell

Any ideas? Or should I see how things go once she's had her flea treatment today?

Also - forgot to add, the cats haven't been scratching at all so I don't think it can be fleas as they usually act up if they get them. Again, I can't see any on T...

Sounds to me just like a common split in the tail - my Dane used to get this a lot - too much wagging and hitting the wall......it's a beggar to clear up too, as they will keep wagging.....

Do I need to do anything? It's not bled much to be honest, I only noticed the blood on it, nowhere else.
I've made up some salt water which I was going to use when it's cooled down but is this advisable or not?