If you had it you'd know it.
Bacterial Meningitius can be contagious. Does the person who possibly drank the water before you have Bacterial Meningitius? The person is only usually contagious the first 2 days of symptoms.
You would DEF. know if you had it... you would have a VERY STIFF neck, headache, probably a fever... vomiting possibly...
The stiff neck is a dead give away. But DO NOT WORRY.
Don't let anxiety take over.
If you are that worried or concerned, make a little Dr.'s appt for a clean bill of health. I'm sure that's what you'll get. =)