Is this braxton hicks?

Hi ladies I’m currently 39+2 and this morning I lost a little bit of my plug. I’d say it was literally a finger size bit of it. Went on with my day no contractions and no more plug. I’ve just literally started with a full belly ache, it is exactly like period pains. Completely manageable, the pain comes for literally a minute then disappears for quite a while on and off.

I’m in the UK so can’t phone hospital until contractions start or water breaks. I’m a FTM and wondering if these pains are braxton hicks or start of labour and with losing a little bit of my plug, do you think something could happen tonight?