Feeling guilty

Sometimes I put my 4 1/2 month old down in her swing or playmat to entertain herself so I can just have some me time. I don't leave her for hours or anything just until she gets sick of it (10-30min) but I just feel guilty for just putting her down to play by herself so I can just chill out on my phone or something for a little bit. I just feel guilty, am I horrible for this?