Feet swelling?

I'm 18 weeks 5 days. My BP has been great thus far but starting a few days ago, my husband and I have noticed my feet look a tad puffy. They are usually very slender (i have very narrow and small feet) and veiny, but at the end of each day starting a few days ago look just a touch swollen. I was 35 lbs overweight before pregnancy

And have gained 5 lbs so far. Worried about preeclampsia now just because it seems awfully early to be having my feet swelling! I do exercise most days (20 or 3o minutes, nothing too intense) but other than that, I'm rarely on my feet tbh, just so exhausted. I could drink more water but I usually get in about 6-8 glasses a day. Should I be concerned? Anyone else feeling with this so early on? Is it an early sign of preeclampsia?