Hi, 
I think you are right. All your symptoms are suggestive of 
hypothyroidism (low thyroid activity) . But I want to know more about you 
1) Age and gender. 
2)Your height and weight. 
3) Any associated symptoms like weight gain, loss of  appetite, lethargy, 
dry skin, change in voice, any external swelling in the neck, disturbance in 
menstruation ( in case of female). 
4)Any discolored patches over body associated with loss of sensation over it. 
I will advise you to do Thyroid function test. (T3, T4,TSH) 
In case of hypothyroidism there will be decreased T3 and T4 and elevated TSH. 
Hypothyroidism might be associated with some complications for which following investigation might be advisable. 
*
Complete blood count to detect low 
hemoglobin. 
*Lipid profile- it is usually deranged in case of Hypothyroidism.