Freaking out

So as I'm afraid to have sex but wanted to feel what it's like without properly having it, my boyfriend put his "ya know" in me without a condom.. However he had a problem so he pulled out like the second he was in.. He was only in me for like 5 seconds.. this happened on Tuesday.. and I was due to get my period on the 1st April but am now 2 days late.. I'm freaking out as I think there might be a problem and my mum will go mental if I tell her as I'm only 15.. what could be wrong??? Any help please😭😭😭 I'm freaking out so bad😭😫