What are the signs of labor?

So I have two doubts. 1. What kind of sign is it when your cat sleeps next to you. By your belly. I’m 34 weeks pregnant. And my cat started sleeping next to me. 2. Also, what do contractions feel like? Is it a sign that I could have my baby early? And that’s why my cat is watching over?. I do have a 4 yr old one. But never experienced what contractions were. Had him C-section. (Early at 30 some weeks.)