Starting annuals from seed

So yesterday night, I started planting some of the seeds. I know it is a little too late now. The frost date in my area is around the end of April. Here is a quick online tool to find out your frost date. So from today we have around 7 weeks left. I have planted:

• Petunia Shock wave Red [7-21 days]
• Impatiens Accent White Hybrid
• Impatiens pink [seeds harvested from our neighbor]
• Impatiens Shady Lady Tango [orange]
• Impatiens Accent Red Hybrid
• Pentas New Look Mix

They say that we should start them 8-10 weeks before last frost. Hence should have planted around Feb 15th. These seeds were bought from Park Seed.