Hooray! It certainly does sound like Jelly bean might be making his/her presence felt! If your plug has come loose, that means that your cervix is ripening - see, it CAN happen naturally for you! All the more reason for you to stick to your guns.
From memory, those first pains were really distracting and very exciting. But, if you're after some advice (LOL, sorry, I'm going to give it to you anyway ) do try to rest while they're not too painful. And don't forget to eat and drink. Maybe if you're not able to rest, do a little bit of walking or bouncing if you've got a fitball.
Your little Jellybean will be here very soon!!!
ETA: sorry to sound like a know-all - I'm just very excited for you