Body having a clearout?

Hi guys ive been up most of the night i had an upset stomach(sorry if tmi) and ive had a pain like a band round the top of my bump that feels like is getting tighter, everytime i move im in agony and now this sounds strange but it feels like ive got a ledge at top of bump stopping me from eating or drinking i had dinner last night and it didnt feel like it went down i was right as ive just been sick(tmi) i have heard some womens bodies have a clearout before labour im hoping its not that as im only 32+2 im going to ring mw at 9am but just wanted some advice until then as to what you think it might be thanks
Lin32+2