To answer your questions:
1) Muscle strain is certainly possible. If there is concern about an abdominal issue, an abdominal CT scan or a colonoscopy can be considered for a thorough evaluation.
2) The testicular ultrasound would not evaluate abdominal problems. The tests mentioned above (the CT scan and/or colonoscopy) would be a reasonable initial evaluation.
3) No - blood tests aren't usually done to look for abdominal or testicular cancers. You may want the consider a PSA test if there is concern about prostate cancer. The colonoscopy would evaluate for colon cancer, and the testicular ultrasound would evaluate for testicular cancer.
4) The mushrooms may lead to any number of GI issues - I would discuss this possibility with your personal physician.
Followup with your personal physician is essential.
This answer is not intended as and does not substitute for medical advice - the information presented is for patient education only. Please see your personal physician for further evaluation of your individual case.
Kevin, M.D.
Medical Weblog:
kevinmd_b