Shadows on Digital Photos

[sophie_1003]

I have a Fujifilm Finepix JX320 which I got for Christmas; I've used the camera a fair bit since then but tonight have taken some and they have a pinkish shadow in the bottom right corner; it is definitely not my finger (or thumb!) although that's what it looks like! And I can't see anything on the lens. When looking at the screen it looks fine and the shadow only appears when the photo's actually been taken. It is mostly on close up shots of coloured paper on a white background that it is noticeable but also took a couple of test photos of our cream setee and the shadow is there slightly too. What could it be and how do I resolve this? TIA

[looobylooo]

can you upload an example photo to here, sophie, using tinypic or something, so we can see the pink shadow?

[sophie_1003]

I think I worked it out; it's something to do with the lights in our living room! Am going to try it again today to see if it happens in daylight and will come back here and post a picture if it does!