As soon as i woke up, my lower abdomen started rumbling like crazy. there is a discomfort/pain in my lower abdomen now. what is this?

Many possibilities: From the less worrying but annoying constipation to the more concerning urine infection to the possibly more serious appendicitis or pelvic infection or pregnancy related problem if sexually active. Very important therefore to be checked out by a doctor as tests may need to be run. Please seek urgent attention if pain is severe, you are vomiting, or feverish. All the best.

Agree w Dr. Ram: These symptoms can occur with many condions. They are just too common to be able to diagnose without more info.