So i brewed up my second all grain batch saturday all went well and hit my og at 1.060. Pitched wyeast 1099 without a starter. Airlock went crazy after 12 hours and lasted for about 24. Now no activity in airlock and Carboy temp is at ambient temp of 70. Down from 75. Wondering if fermentation lasted long enough or if I should open up and check the spgrav? I use a plastic bucket do i cannot see the krausen.