Thanks for your query,
Feeling of pelvic pressure and slight white discharge are usually not very significant in pregnancy
at this stage. But painful contractions may signify onset of preterm labour. So be careful. If you have it again , then go and meet your OBG at earliest. As you are not having any more pain and the baby 's movement is satisfactory, then there is no urgency. You can go your scheduled appointment.
Best of luck and take care..