Thank you for the query.
Your symptoms can be caused by one issue or by some separate problems. Chest pain
should be always checked with heart condition as ischemic heart disease
can act in such way.
Lower abdominal pain
and blood in stool
can be caused by some large intestine issues. If the pain is more in the rectum, fissure is most probable.
If the blood is on the surface of the stool, hemorrhoids can be causing it.
If the blood is mixed with the stool large intestine issue is the reason.
If the stool occasionally is tar like, stomach bleeding should be ruled out.
I suggest you to visit your doctor, have blood work, abdominal ultrasound and stool tests at first. Colonoscopy
should be considered as a next step.
Hope this will help.