No, there isn't any way you'd get pregnant from this. Even if there was sperm on it - taking the worst case scenario, and assuming he had masturbated using that bath sponge, with the water, soap, and time, it would have killed any sperm remaining.
Also, you using it to wash isn't enough to propel them into yourself for the sperm to travel up to your fallopian tubes and ovaries to meet an egg, assuming you had one ready to fertilize.
If you've been on the pill for awhile, it can take a bit for your schedule to resume. You might not get a period for a couple more weeks, or you might skip this one altogether - that's normal. Adding the stress of COVID, and if you're in a lockdown area, and it might be a bit longer. I see from some of your older posts that you're in the UK - it has to be really stressful there. :(
Hang in there, and be gentle with yourself. It's been a rough year. Maybe you and hubby should use separate sponges? Get pink and blue ones if you need to so you'll know which one belongs to who. :)