Aww mama, namamaga lang ang isang side? I'd really suggest checking with your OB about that, swelling is pretty common sa third trimester, pero pag one-sided lang siya, mas better na i-rule out kung walang infection or something else na kailangan i-address ngayon. A few of my mum friends had similar concerns late in pregnancy at nag-relieve lang after talking to their doctors, kaya don't worry too much but best to get it checked na lang para peace of mind mo especially 36 weeks na!