slow responder to stims 1st ivf cycle ?

Hi ladies i am on my 1st ivf cycke after waiting a long 8 years to finally get this far ! I am only 26yrs old so i should respond well but i have not ! They increased my dose of menopur to 300 and went back for sxan to check progress today but they still havent grown as much as they would like ! I am so dishartened and dont know what to do for the best as they are talking about cancelling my cycle , i need to go back wed for another scan to check if they have had a growth spirt .. i have 1x20mm , 1x16mm, 2x12mm and 10x10mm ?? Would u carry on to egg collection with them or cancel? I cant face the fact that we may have to cancel after everything we have been through and to get so far its heartbreaking..any advice would be great xxx