Thank you all for replies,
*I did not receive any vaccinations prior to trip to Thailand
*I am not sure what meningitis feels like, but most of the time the headache is so debilitating that I am almost consciously unconscious, I keep waking up at night due to headache and have very hard time getting up in the morning, very heavy feeling and I am not rested one bit, it is as if my nervous system is constantly irritated, considering random muscle spasms and twitches I would say it is.
*Stomach does have problems now, but I believe it is more likely due to all the antibiotics I have taken over last 3 years, I noticed that even if I do not eat anything at all (e.g. my stomach is just getting warm water), nothing happens to mucus or headache, so I am assume stomach is not the main culprit with head and neck being the epicenter of immense pain.
What I find strange is that Avil or Ibuprofen have no effect on the headache and head pressure at all. It is as if whatever is causing this produces enormous amounts of toxins which are affecting me.