Be very careful here. You're looking for two different things now. You're chasing a feeling that you think you should have because you pray, worship and read the Bible. Such a feeling is not promised in scripture as a reward, if you will, for doing these things. This idea that you should feel God's love because you do something is straight from the touchy-feely modern Evangelical camp.
Also, a lack of love from your earthly father will not somehow be erased by the intellectual knowledge that comes from reading what God has done for us in His written word through His Son Jesus Christ. We see all throughout the Bible God's love for His people, but that's intellectual knowledge really. You're after a feeling, it seems, and there's no formulaic way to achieve that. It's not like if you read your Bible for x amount of hours and pray x amount of times a day, you will feel God's love increase for you in a week or something.
Of course we feel unworthy of love. Scripture tells us what we deserve due to our sins. But you need that feeling of unworthiness to help you understand just how awesome and grand God's love for us is. If you remove that feeling of unworthiness completely, what Christ did on that cross for us, loses its sweetness and beauty. He died for us while we were yet sinners and unworthy of God's love. Christ reconciled us back to God the Father. You can't have this euphoric feeling of love, without knowing that you don't deserve it and can't earn it. Because once you do remove that, then your gratitude towards God for what He has done through Christ, may be replaced by an attitude of entitlement. Like God has to love you because you read your Bible, pray and worship Him.