I have a white hard bump on my tongue it hurts when touched any idea what it is? Been there 3 days

Aphthous ulcer. There are several possibilities. Since it occurred only 3 days ago, it is possible that you have an aphthous ulcer (canker sore) on your tongue which typically will heal within a week or two. If you get worse or it does not heal within two weeks you should get medical attention to properly diagnose the problem.
Get it checked . A bump or growth on the tongue needs to be checked by an ENT or oral surgeon . It could be due to bite trauma, or a swollen gland but a tumor needs to be ruled out. Rinse your mouth with saline, chew carefully and see the doctor within a week.