Listen to mom! :+)
Wait 24 hours to see, some can take even longer.
You can reheat at 24 hours if it's not getting any thicker.

Deanna

Did you use Pint jars or 1/2 pint jars? It's possible that because of the bigger jars they might take longer to set. I used the same recipe for 1/2 pint jars and they came out perfect.

Diane

Because I don't want to have a jam not set, I always try to test a small amount before its poured into jars. a tablespoon of the liquid is put in a small dish and placed in the freezer for only about 2 minutes. If its solid when it comes out, its ready to can. While waiting for that, I will also turn down the heat so that its only slightly simmering, so it doesn't scorch or burn. Usually citrus based jellies will take a lot longer to set up, like maybe a few weeks to a month or more. Even for that, if the citrus jam has thickened while its in the freezer for the two minutes, its usually a good indicator too.

It can take up to a month to gel. Be patient. If it doesn't set by then, you can remake. I don't really like remade jam as it is more gummy in texture.
You can always relabel syrup and only you will know. Lots of us do that !