Been having achiness and sharp pains that come and go in my r thigh but no injury?

Pains in thigh: Pain in the thigh could be referred pain from the hip and/or lower back. Carefully have these two areas assessed as well as an x ray of your femur (thigh bone). You may also need an MRI of your thigh as well to evaluate the soft tissues if your pain is longstanding.

Thigh pain: Consider strain of quad, hams, itb, hip adductors. Also possible referred nerve pain from spine (disc, etc) or thigh (meuralgia paresthetica).