39 weeks pregnant today, period pains past hour!?

hi so babys engaged so my midwife said last week and its just a waiting game now, ive had plenty of darkish yellow discharge for a while now, had the sharp 'lighning' effect down below really really bad off and on mabe 3 times a day for the past 4days seems more painfull and today ive had period cramps..not painfull but they are noticablly there and just wondered if it is early stages of labour?? ive not lost my mucus plug i dont think and my waters havnt broke.. now if these cramps come and go can it still be early labour?? advice please!! xx