I am new to itunes and signecc up fgorc3 free months uding my credit card gor th9e 9.95 service...i have slreadg been charged slmost 40 d0llars fiir music i dont even want

I signed up for 3 free months of iTunes with the exception I pay 995 at the end of the three months and I put my credit card down thinking I have 3 months to discover iTunes and I've only downloaded for albums and I've already been charged $40 what the **** is going on I don't want this music if I'm going to be charged for it it's it's misleading for 1 please respond