In the past i've used a rampant rabbit elite, which has a girth of 3.75 inches, but i treated myself to a rampant rabbit thruster which is 5 inches round. i have lube but am starting to get quite stressed with my little self as it doesnt seem to go 'in' whereas my previous vibe and my (slim) boyf dont have a problem... any help? im starting to think i have wasted my money!!