Shaft change and swingweight

Hi

I've recently changed the driver shaft in my 910D3 from the MFT A'hina 72g stiff shaft (45" length) to the Rombax Type-X 75g stiff shaft (44.5" length).

Could someone please let me know how this would have affected the swingweight, and how I should go about increasing it as I feel as though I'm 'losing the head' a bit when I swing hard.

I changed because I was after something lower launching than the A'hina which tended to give me virtually no roll after landing.

Many thanks in advance

Jamie