It's quite likely that she didn't work on Friday. I really don't think she is angry with you - this is a hectic time of year, and email messages do get lost sometimes. It's a good idea to email a list of possible dates and times. If you do that, you are being constructive and helping her help you (which is her job! You are not being a burden. She's there to help you through this, don't forget that.)

I still think it's awesome that you got into the summer research programme.