My hands ache all the time?

Since starting my new job about a month ago my hands are always aching. They don't even get better over the weekend. They have actually got worse this weekend. It's 6pm on Sunday and I'm gonna take some pain killers. I thought my bones would get used to it but like I said it's been a month. My job involves a lot of gripping onto massive blocks of sponge and moving them around a lot. They weigh about 80kg (176lbs). I do this all day. My fingers and hands constantly ache. I've got quite soft and small hands for a 29 year old man. Am I likely to be doing any long term damage?