My mav was really bad after my 6 wk checkup. This was my second child too. It took about 8 mths to get diagnosed. My neurologist said that it could be because of hormones from breastfeeding. My little guy was Hungry all the time! The dr put me on tablets (can't remember what they were called). I stopped taking them as they made me really tired! My youngest is 3 now and I still suffer from mav, but the vertigo isn't too bad. It's just the brain fog and feeling drunk that I have now. I am not doing anything for it at the moment.
I am sorry that my post isn't positive, but I remember going through mav with 2 under 2 and I really feel for you! I hope you find a good dr soon who can help you. All the best!