Is spermicide lube and withdrawal effective enough?

I am getting on the pill as soon as I can, but it won’t be for another few weeks. I am wondering if a lube with spermicide combined with withdrawal would be okay for now. I don’t get periods at the moment due to my previous birth control option so I have no idea what’s going on and whether I’ll ovulate or not and if so when that would be. We cannot use condoms of any type so those are not an option. Thanks for any input