I feel like my belly got smaller this week instead of bigger. Is this normal?

Hi everyone! I am 19 weeks and 4 days today. I am high risk due to having type 1 diabetes and have had 1 miscarriage. I have been dealing with nausea and baby is picky about foods I eat. Alot of what I used to enjoy makes me sick. I think I have felt the baby move but it definitely has not been consistent. I am so paranoid that something is wrong, it's so hard not knowing what is going on in there. I have been taking weekly pictures. Lately I have felt like my belly has gotten smaller instead of bigger and after seeing my pictures, it really seems that way. Is it normal for the belly to fluctuate a bit like this? Or is it just because I am wearing a different shirt? Please help.

This top one is today's. And the next one is last weeks.