Have anybody else felt this way?

I love my bf to death weve been together for almost 2 years and this has been my first relationship that has ever gotten serious every now and then we do argue and it does get hard to get through it lately ive been feeling nervous when i see other couples my age who have gotten engaged fast or had babies and beoke up. Im like ooooo my god what if we dont make it, is this really gonna last like im thinking or is it all fairy tales. Have you ever hurd im not scared of lions, tigers and bears but im scared of loving you. Thats how i feel