JonPenny1981, No, I'd just wait a day or two more. My last two smack packs took a little while to start up. I used a Greenbelt Pale Ale smack pack and this one didn't swell up much, despite 4 hours of warming up to about 74°F. After 18 hours the top looked flat without a single bubble. I thought I was going to have to pitch again. I went to work and 12 hours later bam, lots of foam.