It all depends on you answer where baby is. Some people have pains lower down, others in the back and others all over the tummy. Best way to tell is they feel like period pains and each one will gradually get stronger, peak and then the pain will fade. Contractions will also get stronger and more painful as you get more of them. If your concerned call the hospital. If you wait for a bit you will soon know if your in labour or not. Good luck!
for me, my whole tummy goes rock hard so that feels uncomfortable then there is extreme pain lover down that slowly comes and then slowly goes, then my whole tummy relaxes until the nest one starts, then when they get close together its all blens into one big ouch :)