4 days pp feeding advice needed

My lil girl was born 4 days ago and from being pregnant I was so determined to only breast feed! She latched perfectly at the hospital but since being home I’m struggling to get her to latch effectively! Sometimes she latches straight away , sometimes she gets to frustrated and doesn’t latch at all! Iv ordered some nipples shields to see if that will help. Since bf is becoming a struggle Iv started to pump every 2 hrs and getting around 2/3oz but also been supplementing with formula when needed. I always offer the boob first! Sometimes she will enjoy the boob but only for 5/10 mins then I have to bottle feed. I’m going to keep trying!! And hopefully increase my milk supply so I can take away the formula all together. I’m going to keep offering the boob first before anything else.

Please tell me I’m doing the right thing?

Second time mum but first time bf!

Any tips/tricks/advice much appreciated!!