sorry I wouldn't be a good help but what I think you could do for now is trim/cut off the mats you see/find.

spaniels can be difficult to have a proper cut so I agree, take her to a pro.

she's a beauty! the last picture of her is too cute..with her "hush puppy eyes"!

oh, there was a "summer grooming" thread you can find by search button, you may get more ideas from there and good luck on your decision.