Buying ketone testing sticks is a good idea. Then you can test & if they are getting high you can make a major effort to drink lots of water.
Eating as much as possible is a very good idea- I lost kilos due to HG. It might sound great to be thinner than when started pregnancy, but a nasty cold & gastroenteritis later it's really bad to be too thin.
Re the 9 weeks thing- my HG finished at 16 weeks. Vom etc from week 6 to 16. I did wonder if it would ever end. A bit scary. But basically it ended when the placenta took
over making the hormones.
If you read the HG support thread you will see the time varies from person to person when it goes.
Lucinda is a star, keeping everyone supported on there 
I went tru 3 drugs them got 1 that worked for me. Basically they start you off on the cheapest safest drugs, then work your way along until one works.
My path was:
Cyclizine (bad reaction to this, but works for lots of people)
Stemitl (did nothing for me, again works for lots of people)
Maxolon (finally this worked!)
Onedastrol (can't spell it, not as safe in pregnancy, and expensive, but if you are at deaths door then it's a option)
The HG thread has links to proper info on these drugs (can't link sorry, on iPhone).
Key thing is- they are safe to take.
If you need em, you need em.
Remember the end result can escalate-
Dehydrated, ketones rise, feel sicker, more dehydrated.
Result is you need a drip to get rehydrated, plus the anti sickness drugs to stabilise the sickness.
I recommend you try to avoid this unhappy path (ie don't do what I did!)
Drink drink drink!
Then drink some more!
Good luck, I really feel for you