Hi,
I'm sorry your beardie is having problems. If you've posted this info before I apologize for asking but it will help.
Are you sure it's blood?
What are the 3 temps in the enclosure, the basking surface, hot end, cool end?
What substrate is your dragon on?
What size bugs do you feed him?
You said he is straining to pass his stool. Is the urate {white part with stool} hard or soft, you'll have to smash it with a gloved finger or lay tissue over it and smash to feel it. It should not be hard like chalk or dense. If it is, he can be dehydrated. It should be soft but hold it's form til smashed, good consistency is a bit softer than custard.
To help with passing his stool, soak your dragon 2 or 3 times a day in shallow warm water, enough to cover the waste vent. He will absorb water thur this vent which will help
hydrate him and some water will remain in the bowel to stimulate stool to pass.
Yes you can give a few drops of olive oil, veg. oil or mineral oil mixed well into about a teaspoon of baby food apple sauce.
Although worms and parasites usually cause loose, runny, mucousy stools that smell much worse than usual, he does need a fecal done because you are seeing what you believe is blood along with the straining to move his bowels. You can check on line for mail fecal testing and see what you find. Some places will have you mail a sample for examination and a small fee. They don't prescribe meds for it usually. You can contact an expert member Tracie...Drache613 is her username....based on results, she may be able to recommend a med if needed and help dose calculations based on weight.
Beardies will want to hide when they don't feel well, that's what they would do in the wild, so it's no surprise he doesn't want to bask. I'd gently put him back to basking when ever you see him not basking. He needs the heat for proper digestion to occur and he is already having gut issues .
I hope this helps. Others will come along with suggestions too!
Amanda