Does it feel different?

Not sure if this is stepping into where i don't belong but I'm just so worried. I'm currently 31 weeks with my first but there's a good chance I'll got into premature labour and I'm just wondering if it feels much different to a full term labour. I haven't had the steroid injections yet so I'm really worried i won't realise that I'm in labour if my waters don't break and then not have enough time to have both shots as they've got to be done 24 hours apart.