Depending on the cock, it can be painful. Lots of lube and lots of patience.
Another interesting fact. Sometimes a woman with limited sexual experience will "lose her virginity" without fully tearing her hymen. Sometimes this happens when a different, larger man is introduced to her. This can result in what can be considered "severe *******" but is actually just a continuation of what was started earlier in life. The initial tear to the hymen builds up scar tissue, sensitivity and additional capillaries, but you will be okay.