I have a wisdom tooth coming through at the back top left and i noticed a lump and i was feeling it with my tongue and it feels like its coming off i can move it i don't think its food im pretty sure its my gum is this normal?

Yes, it is probably the gingival tissue and it will slough off when the wisdom tooth comes out. You are fine if there is no pain or no sign of infection.

It's probably an operculum, a flap of the tissue that used ton overlie the erupting wisdom tooth. Just keep the area clean as it dissolves back. If it's sore, or if you are biting into it, see your Dentist, a Periodontist, or an Oral Surgeon