I Feel Heaviness In The Upper Part Of My Neck With Headache. Is It Because Of Sinus Problem ?

I have heaviness in my head and of late I feel the back of my mouth is full and my mouth opens as there is too much pressure aggreviated at the back. I feel heaviness in the upper part of my neck, headache sometimes at the centre, other times on both or one side of my head. I sometimes have problems with breathing.... I sometimes have to put my head facing up to feel a bit better as I feel very heavy on my head when I am in normal position. Please let me know what type of sinuses am suffering from and what I can do to clear it all out.