There are several signs to tell you if your thyroid is low. Years ago, Good Housekeeping had an article about low thyroid. I was at my local beauty salon and started answering questions and all came out yes. So my next trip to Dr I asked him about it. They did the blood test and sure enough my thyroid was very low. I can't remember questions except for being tired, no energy, low luster hair, losing hair, not sleeping at night. I would imagine the internet would give you any info you might need to know. I was amazed how much better I felt after several months on correct medication. Take care of yourself....we all have UFO's to finish!!