Brief Answer:
Probable sinusitis or tension type headache.

Detailed Answer:
Hello

I read your questions carefully and I am sorry about the headache you are experiencing.

I also had a look at previous questions you had made and I notice that in the previous days you went through a cold, with a running nose. That makes me believe that you might have sinusitis (sinus infection) which is a common complication of a common cold and could present itself precisely with headache in the front of the head, so that is the most probable cause. Often it is accompanied (although not always) by greenish/yellowish discharge from your nose or down your throat causing cough as well.

Management consists in decongesting and antiinflammatory products to facilitate drainage of the sinuses as well as sometimes antibiotics. For the pain you should take over-the-counter painkillers like acetaminophen or ibuprofen.

However the diagnosis must be confirmed by physical exam before antibiotics are considered so you should discuss it with your primary doctor which might refer you for a ENT (ear-nose-throat) specialist consult to confirm the diagnosis.

Another option might be simply a tension type headache, the most common primary headache (primary meaning with no identifiable cause), often precipitated by stress, for which the treatment is the same painkillers mentioned above acetaminophen or ibuprofen.

I wish you a speedy recovery.

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Brief Answer:
Anxiety might be a factor.

Detailed Answer:
Once every two days is not out of norm, normal frequency of bowel movements is from a couple of times a day to three times a week. It's only if you have considerable strain due to hardening of the stool that one can say to have constipation problems. You should try to drink a lot, eat more fiber foods (vegetables, whole grains, fruits), reduce stress.
Regarding your stomach pain, if you do take them avoid, smoking, coffee, tea, eat at regular hours and again reduce stress. Drugs which reduce acid production like omeprazol could be used.
The causes of both stomach ache and constipation can be many, initial symptoms can be the same for different causes, often nothing major, in your case you have a very common predisposing factor for both of them, anxiety, which can link the two together.
However if symptoms persist and haven't ever been present in the past, then you should consider tests like optic fibre endoscopy.

I hope to have been of help.

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Brief Answer:
Probable IBS

Detailed Answer:
The combination of constipation and diarrhea is often in the setting of Irritable Bowel Syndrome (IBS) which as I hinted before is often associated to anxiety problems.
Of course it might also be just a case of a passing gastrointestinal infection.
Neither is serious though, try to relax.

It is good that you are having endoscopy, so that conditions like ulcer or a less likely tumor can be definitely excluded.

In the meantime, regarding my previous recommendation for painkillers about your headache, perhaps it's better to leave Ibuprofen out for the moment as it could exacerbate an ulcer, acetaminophen is safe.

Wishing you good health.

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