I've had similar experiences.

First time I ate cannabis I used 1 gram and made a firecracker. Put it in the oven for 22 minutes at 320F. I didn't feel anything.

Second time I used 2 grams and made a firecracker once again. Same temperature. After 45 minutes I felt buzzed and it lasted for 7 hours or so. A buzz lasting 7 hours sucks. Extremely weak high for so much bud used. Not worth the wait/trouble.

I would have had the same effect if I smoked .25