One more month till labor.. not sure i can handle it!?

So I'm exactly one month from my due date and felt great up until now. Since Thursday everyday I wake up nauseated and the feeling of having to throw up lasts all day. I have constant pain in my left leg (this started a few weeks ago) and if I move too fast I get pain in my stomach. I've also had period type cramps lately. Could any of these be signs labor might be sooner? I asked the doc what to look for and he said the only sign ill notice that will show I'm in labor is my water breaking. He said if it doesn't break I'm not in labor. Are there any other signs?? Will I feel anything else? This is my first pregnancy so I'm not sure what to look for and that's all he told me to look for was water. Thanks!