4 month border collie/GSD – shy at potty time-it’s been 7 hours, no pee or poo-day 2 pad trained previously-22 outside 5-10min adventures-Should I put a pad down before she hurts her bladder???

Advise needed-I am about to put a pad down, any hints would be appreciated.

History: Female 4 months border collie/GSD, vet checked, puppy shots. Birth home only used puppy pads, we had two overnight visits 2 and 3 weeks ago, she used pad by door consistently but refused on outside on a lead. Crate was late on order so my husband is picking one up this evening. She is very smart and wants to please, she loves my resident Anatolian shepherd who is super patient and chill, and has followed cues for: sit, look at me, lie down, and go to your spot. She cued off her name for a “find me” game which was very impressive for day one.

Day 1 – Pad was left at door, used gates to limit access to most of the house. Used a schedule of outside on a lead (also new) every hour and before and after activity change-eating, napping, playing. I was hoping to pick up her cues of when she needed to go but she managed to get to the pad and go 4 times without me even seeing her go near it – zero times on the lead outside… we went outside 17 times.

Day 2 – We modified a crate out of a gate system for overnight, she slept good. My partner had a fail with the lead in the morning and she got the spot her pad used to be. I have her on a house line since this mornings fail at 7am, we have been outside 22 times it is now 4pm. She had her last drink at 1pm, and last snack at 2pm. I have a quiet spot outside 10x10ft with a used pad, on a 6ft lead, I stay quiet with a pocket full of treats but she looks and acts very nervous. She’ll sniff and circle and then just lay down shaking… she is very confident inside and on the two times my resident dog came out with us and peed 3ft away from her, extremely nervous on her lead alone.

I am impressed with her bladder control but actually getting worried at this point that she’s going to cause damage… never seen refusal to go outside like this before. Suspect very limited leash/outside exposure at birth home. It is cold out -9 Celsius.

Any advice appreciated! at this point I’ll give her two more trips outside and then put down a pad at her spot by the door-and just try and focus on building some confidence outside???

Thanks to those who read and responded

UPDATE: she peed in the sunroom! It’s in between her spot inside and her outside spot. I let her play with my resident dog without a tether outside. I gave her lots of praise and put some pads down in the sunroom by the outside door in the sunroom. She was very confident outside without the tether so I think it was the leash making her nervous. I have a really large backyard with a partially frozen over pond so it makes me nervous having her untethered even if monitored, she followed my resident dog like a shadow though. Hopefully we can transition fully outside when she gets the hang of this as an in between… at least she didn’t explode!