Comedy flailing - advice gratefully received

So I have a new board and while I know it's going to take a little getting used to - there are a couple of things that I'm struggling with.
Basically I've had a play in the white water just to get a feel for it before going straight out the back - I can stand up no problem - but when I try and get on to green waves I am having more trouble.
Now the first couple of times I went out was pretty messy, small and low tide - I managed to get on a couple of green waves and have a fairly short ride, so far so good.
This morning it was 3-4ft swell, high tide, which is usually my favourite time to go out as it's not too big and the waves tend to be a bit softer.
But today I definitely struggled to catch waves - paddling, this will improve with time, I changed position so I was a little bit closer to the inside, but found that when I caugh the wave the front of the board pointed straight down - I wouldn't say it was perling but it was suddenly extremely steep, trying to stand up on it, did not go so well.
I also found that the board shot out from under my feet a couple of times - this is a problem with my pop up no?
Any suggestions, advice, tips gratefully received
Basically I've had a play in the white water just to get a feel for it before going straight out the back - I can stand up no problem - but when I try and get on to green waves I am having more trouble.
Now the first couple of times I went out was pretty messy, small and low tide - I managed to get on a couple of green waves and have a fairly short ride, so far so good.
This morning it was 3-4ft swell, high tide, which is usually my favourite time to go out as it's not too big and the waves tend to be a bit softer.
But today I definitely struggled to catch waves - paddling, this will improve with time, I changed position so I was a little bit closer to the inside, but found that when I caugh the wave the front of the board pointed straight down - I wouldn't say it was perling but it was suddenly extremely steep, trying to stand up on it, did not go so well.
I also found that the board shot out from under my feet a couple of times - this is a problem with my pop up no?
Any suggestions, advice, tips gratefully received