Is this Some kind of contraction??

I was a first time mother and didnt know how contractions were like. It wasnt like wad people told mi that kind of terrible menses pain. I had very bad tailbone pain on first night but i managed to fall asleep from the pain. The following day midnight i could not and the pain was very bad thou i could still pace ard my room. Hubby insisted bringing my to a&e and true enough i was already 4cm dilated! I think if worried better go and check? The labour ward nurses told mi some experience front pain, some only back and some have both.. until now i dunno whats contraction until the later part when you feel very terrible. Wishing you a smooth delivery in advance!