TTC questions including Breastfeeding possible false negatives?

So I am two days late for AF and 17 DPO but I am getting negative tests! I have had a little pain in my abdomen recently and am not sure what to do... should I wait a few more days to see if AF is just off this month or call the dr to see if they can test for me ? I almost went to an urgent care because me abdomen was bothering me quite a bit... I am currently weaning my daughter from breastfeeding so I didn’t know if that could mess up the results.... could I be getting a false negative?

Any advice would be great