A technical thing, really. I want to edit my first post in my novel thread, adding some stuff and I wanted to ask if that counted as a new post and do I need two more reviews for it?
If you want to add stuff then you might want to reply to your own thread and post a part 2. If you're going to edit/add to the original then try to make it very clear that there's an update. If you're editing your writing and posting an updated version, then the mods would like you to post as a part 2 - or 3, etc - don't delete/replace what you had there before. Regardless of how you handle this your entire thread only counts as one post in terms of reviewing requirements. That is, assuming that you stick to the same story. You could see that as a reviewing loophole, but it isn't really... You generally receive more-or-less what you give here, I think. So no, you don't need two more reviews. You're good to go. Though it's always a good idea to do more reviews than the minimum.
Please do not edit a draft that people have responded to. Instead, post your revisions at the end of the thread. That way, everyone can see the progress from one draft to another, and can see the original context that early feedback was posted about. The story (or poem. etc) is yours, but the thread belongs to all thiose who contribute to it. Keeping the process transparent is to the benefit of all who read it. Seeing the kind of critiques given, along with their context, helps oter members learn to improve their critiquing skills by finding new things to look for, and often seeing the effect of the accepted suggestions.