I noticed a large bump on my 4th metatarsal of my right foot. doesn't really cause pain but feels really strange? don't know where or what caused it.

Causes: The location that you described typically is where the tendon courses over the fourth metatarsal. Tight or ill fitting shoe gear can irritate the tendon. The tendon damage as a result causes a lesion on the tendon that is called a ganglionic cyst. Other lesions in that area could include a lipoma. Consult your podiatrist for the correct diagnosis and treatment plan.

Muscle belly: If it's soft and squish and close to the ankle on your 4th metatarsal, it may be a muscle belly of the extensor digitorum brevis. It's common to enlarge or decrease with hydration or activity. If it's further anterior and closer to toes, it may be a ganglion cyst or lipoma. See your doctor for referral to a specialist. I hope this helps, if so please vote or follow me. Thanks and best of luck.

Is it: Hard or soft? Can you move it around? If so its likely a ganglion cyst otherwise could be a number of things. Get it checked to play it safe and good luck!