I made the same mistake as you and read up online about Lithium BAD mistake.

Yes it's important to educate yourself about anything that interacts ( for instance its advised not to take any Non steroidal anti inflammatories or Ibuprofen ) and to make sure you keep you salt intake steady.

Absolutely important to drink at least 2 litres of water a day.

I have been on it for about 6 weeks now. I started on 400mg had my bloods checked after 2 weeks, then upped to 650mg and having bloods checked next week ( 3 weeks after increase )

It is a real pain in the *** to take but for me personally it is working and now I have stabilised and am drinking my water I am feeling so much better.

Meds are like everything else in life what works for one doesnt for another and lets face it, if they work people are less likely to post about it online thats why you mostly only read the bad stuff online.

If as you say you are getting your bloods checked weekly then you are in very very good hands.
it takes a long time to suffer from toxicity it doesnt happen over night, my pharmascist told me that she has never had a pateient with it and the only one she heard of was because they hadn't had their bloods checked in 6 months.

Please try not to worry ( impossible I know ! ) give the lithium a shot and it might surprise you.