The presence of blood in your tissue is due to damage to the blood vessels in the rectal mucosa due to straining & impaction
of hard stools.
The causes of hard stool/constipation
1. Functional cause- due to decreased gastric motility
2. Irritable bowel syndrome- constipation predominant type.
3. Less consumption of fiber rich foods
4. Less fluid intake
5. Prolonged use of certain medications.
6. Hormonal & Metabolic causes, etc.
So, after your work at the sea is over, kindly consult a Gastroenterologist
& get a proper physical examination done.
Investigations like Ultrasound
scan of abdomen, Colonoscopy
& contrast studies will be helpful to rule out any pathology in the Gastrointestinal tract.
Till then, symptomatic relief can be obtained by intake of Laxatives & stool softeners, but their regular use is not advised.
However, as long as the underlying cause is not treated, symptoms will keep recurring.
You can ask me any further query on this website using the below link: http://www.healthcaremagic.com/doctors/dr-polash-sannigrahi/64925
There is no need to worry, you will be fine.
Wishing a good health.