I'm going to bet a pine needle didn't puncture your tire - unless it was made out of brass. Given that you don't have a pump, chances are you were running on low pressure and possibly pinch flatted it over a square-edged bump.
Learning how to fix a flat is a vital rite of passage for a cyclist. These days, I have a spare tube, a patch kit, and a CO2 canister in my saddle bag, and I routinely listen for leaks and bounce my tires at stoplights to confirm that I'm at adequate pressure.
As for pumping tires - almost anybody on this forum will suggest at least checking tire pressure with your thumb before every ride. I like my tire pressure in a consistent range, so I top up my tires before every ride. Some people even run latex tubes, which pretty much demand to be reinflated on a near daily basis. But even if you run standard tubes, slow leaks that take hours (or even days) to be noticeable are definitely a thing, and valves can get damaged, especially somewhat fragile presta valves. So always check.
Worst case, I think you can buy tires pretreated with Slime (a sealing compound), and you can even get plastic puncture strips to line the insides of your tires. Of course, all of that adds weight, rolling resistance, and ruins the ride, so might just be worth learning to fix your flats yourself. Besides - fixing your flat yourself = $4-8 for a tube, taking it to a shop is likely $15-20, so you win out in the long run.