Pseudeuophrys Lanigera egg sack?

[spellsparrow]

Hi, I've never kept spiders of any kind before but I captured a female pseudeuophrys lanigera that was jumping around my bed a few weeks ago, I accidentally hurt one of her legs trying to get her to put her outside again, said leg was promptly self amputated. I, feeling guilty, decided to look after her. She was quite content eating small fruit flies jumping around and such. About a week and a half ago i noticed she had made a thick nest in the top corner of a card box i left in her enclosure, much thicker than the normal retreats she had made. At first i thought she was moulting or something but she came back out after a few of days, then unfortunately, i found her dead yesterday. No idea why, throughout the time i had her she had been eating, exploring and had plenty of places to wander around, hide and jump on. I noticed a slight drop in weight I think, kind of hard to tell when she's 4mm. She was a little less sprightly for a week or so I'm sure. Anyways, post mortem, i found this amber ball inside her nest, it was impossible to see without disturbing her, and I'm wondering if it's eggs inside or something unpleasant, if anyone could help me identify. If it is an egg sac any idea if they could survive without their mother? If so how would I go about helping them? I would like to honour her if possible, I'm quite upset that she died after having brought her under my protection. Sorry the picture isn't very good, I did carefully move it to get a pic, its a ball shape inside.