Is It A Symptoms Of Thyroid And Should I Take Treatment For It?

Hi, I am 23 years old female. during the year of 2007, i was told that i have thyroid problem and the blood test showed that my T4 is 0.63 and TSH is 21.76. The tablet that i was adviced to take is Thyroid elthroxin 50 mg. For past 6 months, i dint continue to take the tablet, also i dint face any problem. my mentrual was regular. Was in normal weight. My health was completely good. But now for the past 2 months i feel some heavyness in my neck. look like some swelling in it. often suffering from sore throat, highly increased in weight. Could you please advice whether is it again the symptoms of thyroid and should i take treatment for it. Often i feel my neck is very heavy for me, that too as soon as i take my food.