Gestational diabetes test results

So I looked at my test results today after my 3 hour test I took August 30th and I was good from the start, 1st hour after the drink I was high only by a tad, no big deal then 2 hour mark I was at a good range no big deal at all but the 3 hour mark I was very low and I’m not sure what this means. Has anyone else had this problem snd it been fine? Seeing my doctor Monday so I’ll get the full story from her but just want to know ahead of time what could possibly be wrong with me so I can prepare myself! Thank you in advance !