What Causes Scanty Periods With Back Pain And Sore Breasts?

Hi, Im 29, wt 40 kg, trying to conceive for 2 months now, never used OCPs. earlier my periods were normal but for 2 months im getting very scanty periods lasting 2-3 days with lots of lower abdominal and back pain with sore breasts. My Pelvis USG came back normal. My gynec asked for hemogram, ESR, thyroid test as well as Mantoux test?? will i face any difficulty in conceiving??