what does this mean??

okay, so me and my boyfriend were about to "do it" for the first time together and everything was going good before then he couldnt put his dick in... he tried it in 2 positions then we stopped and he fingered me to try to make me more wet and then he tried again and it just wouldnt work... omg i have no idea what this means and why it wouldnt go in and neither does he. BTW we are both teenagers so we dont know everything about sex yet lol please help