Thyroid problem ……? ?

So I’ve always had irregular period , i’ve been really depressed , and I been kinda moody as well . My neck is rather chunky ( swollen ?) and I been losing hair . I can never lose weight no matter how healthy I eat . I been exercising ALOT trying to lose weight for MONTHS ! since January and I haven’t lost weight. Could it be a thyroid problem ? If so what will be done about it ?