I had a bunionectomy 5 days ago. The doctor told my husband and I that he would give me more pain meds for it. Are there any drawbacks?

Not severe. Yes, recovering from surgery can be painful, but the more you elevate after surgery, the less you swell, and the less you swell, the less you hurt. Your surgeon will give you a boot or shoe, and pain medication, too: don't be afraid to take what has been prescribed by your surgeon. Most common side effects to the pain meds are sleepiness or some nausea. Take the meds with food to prevent this.
Not if used right. Bunionectomies can be very painful procedures. Most patients experience moderate to severe pain for 3-4 days; mild to moderate pain for 3-4 weeks; and mild pain for up to 3 months or more. Pain medications are safe when taken appropriately as directed. If you take only as much as you need, and stop taking it when the pain settles down, you should be fine.