AI just cooked a fruit cake and on top it felt firm and the skewer was coming out clean, I left it to cool for 30 mins in the tin and when I took it out the bottom seems quite sticky but I don't know if it's not cooked or if it's just a bit sticky from the moisture of the cake and sitting on the grease proof paper... Help!

I don't trust a skew when I make fruit cakes as I found the results too unpredictable.  I have a very fine knife that I stick in the middle.