Fibilou, congratulations on the birth of your daughter !
It sounds like she takes a few sucks to get the actual nipple to the back of the mouth. The nipple should not get sucked at all, it is more of an upwards milking motion of tongue against breast and roof of mouth if that makes any sense at all?
Look at some of these videos; I found them v useful. Google Dr Jack Newman and Kellymom for lots of evidence based BFing advice.
Also, have you tried holding her in the rugby hold (hold in left arm for left breast with baby's head in your hand, bum under your elbow and feet behind you) to get her on at a different angle to allow your nipple ot heal?
And then there is always Lansinoh...
My HV always stated that the expression "toe curling pain" was coined by a BFing mother with a bad latch .
BTW, not saying anything disrespecful about you MW, but lots of MWs/HVs/GPs do not know a lot about BFing. Is there a BFing group you can go to? Or contact La Lache League/Breastfeeding Network or similar? Or Bfing adviser at the hospital you delivered?
Good luck! She is only tiny; it does get so much easier with time and practice.