I went on a coffee and lunch date with this girl that went well. Shortly after, my grandmother passed away and I never called her back. I didn't do this intentionally, it just slipped my mind and after a couple of weeks I decided it had been too long and I chickend out.

5 months later I bump in to her and I immediatelly apologized without making any excuses and she forgave me. I asked for her number, set up a dinner date and went out with her on a Wednesday. The next day, she sent me a text message saying that she had fun and that's she hoped that I did too. I replied saying that I had great time and left it at that. I want to call this girl back and my question is does it look desperado if I call her on a Friday or Saturday?

No you will not look desperate. Call the girl! Don't play games.. She seems to be interested in you so call her when you feel like it even if it's early.. You already blew her off (untentional or not) in the beginning, don't make her wait again for your call. Throw all the stupid dating games rules out the window. This seems like a nice girl for being so understanding, I'd hang on to this one.

No it doesn't often girls think you have given up on them if you haven't called them by Fri or Sat and they really think you are not interested if you do not call them at least two or three times a week.
She may be looking forward to you calling and getting together sometime during the weekend.

Thanks, you were right. I just talked to her and she was happy to hear from me and we setup another date :)

Well calling her the day you got her text should have been good,
And chickening out will make you end up that crazy old man with 10 cats that lives alone.