Why Do I Feel Fuzzy And Heavy In My Head?

hello I am 36 years old, 180 cm high and wirgh 79. I had a venus sinus thrombosis about 6 years ago, for which I had brain siezures and became parralysed on my left hands side . Recently my head has been feeling fuzzy and heavy (no headaches but some small tingly feelings). This has been happening for about a week now and the last couple of days I have been feeling faint a few times (which goes after about 1 minute). I must add that I sometimes feel like this if I am ill with something minor like food poisoning or fever ect, which I don t feel I have. I admitted into hospital and the doctors checked me over for signs of a stoke (strength, behind my eyes, balance ect and they also checked my heart. But everything was fine. They also checked my blood which showed was a little high in colestrial and the thickness was a little higher than normal (but doctor said it was nothing to worry about). I left hospital with the following medication Celebrex, Serc 24, Stugeron 25, Rivotril and Simvastatin. One other thing, I had been smoking cannabis for about a month before a became ill. Could this have some effect on the feeling in my head? Can you think of anything it could be? Thanks for your time Graeme