Your symptoms are suggestive of a hormonal
imbalance. When the oestrogen hormone levels in the body are high, you may experience nausea
and missed periods. Weight gain and excessive sleep are also due to the imbalance in hormones, so is the spotting. I suggest you to see a gynaecologist for a total assessment and you may also be referred to an endocrinologist
. This happens in many cases and you need not worry. The outcome of treatment is almost very positive and conception has been seen in majority of cases. Good luck.